JP3474753B2 - Erasable image forming material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention
It relates to an image forming material that can be erased. [0002] 2. Description of the Related Art In recent years, with the spread of OA, various types of information
The amount of data keeps growing, and the output of information
It is increasing. The output of information is
And hard copy output to paper by printer
Be represented. However, for display output,
Large circuit boards are required for portability and cost
There is a problem from the point of view. Also, with hard copy output
Uses a lot of paper as a recording medium when information increases
Therefore, there is a problem in resource conservation. Only
Also reproduce paper printed by printers and copiers.
Requires a large amount of bleach and water to regenerate
Will also be higher. Therefore, using an erasable image forming material
Print information on paper, erase this formed image,
By reusing the reused paper,
It is considered to reduce the use of qualitative paper. Conventionally, images that can be erased by applying heat
An image forming material is disclosed in, for example, JP-A-7-81236.
Have been. This image forming material is colored with leuco dye
Compounds, developer, and organic phosphorylation with elimination action
And a compound. [0004] However, the image formation comprising such components
If the material is used, the paper is returned to a blank state due to insufficient erasing
It is difficult. For this reason, erasable image forming materials
Has not yet been put to practical use. [0005] SUMMARY OF THE INVENTION An object of the present invention is to provide an image
Can be easily erased after formation
Providing an image forming material that can maintain a stable state,
To effectively reuse paper. [0006] SUMMARY OF THE INVENTION Erasable images of the present invention
Forming material contains coloring compound, developer and erasing agent
Erasable image forming material,The erasing agent is
A cyclic sugar alcohol and a hydrid other than the cyclic sugar alcohol
5-membered or more non-aromatic cyclic compounds having a loxyl group
Or induction of a cyclic sugar alcohol other than the cyclic sugar alcohol
Consisting of conductorIt is characterized by the following. [0007] [0008] BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.
I do. The image forming material of the present invention comprises a color former and a developer.
Formation and erasing of images by using elimination agent
I have to. First, construct this erasable image forming material
The operation of the basic components to be performed will be schematically described. Present
A color compound is a color that forms a colored image such as a character or figure.
Is a precursor compound of the element, and the developer is
Color due to interaction (mainly transfer of electrons or protons)
It is a compound that develops a coloring compound. Also, the erasing agent
Preferentially to one of the color developer and the coloring compound
It is a compound showing compatibility. Composition of an image-forming material comprising these components
The system can take the following two states when solidified.
You. That is, (1) the erasing agent corresponds to the equilibrium solubility
Mix with the coloring compound and developer in the amount of
Color developing compound and developer exceeding the equilibrium solubility of
Phase-separates with the erasing agent, and the color-forming compound and the developer
State of color development by action, and (2) the developer is a color developer
Or take in large amounts of color-forming compounds beyond the equilibrium solubility
Color, the interaction between the color-forming compound and the developer is reduced, and the color is erased.
State. [0010] The state change between the colored state and the decolored state
Is performed according to the following principle. Here, the above composition
When the system is in a molten and flowing state, the erasing agent removes the developer
The description will be made on the assumption that the substance is preferentially dissolved. At room temperature
Indicates that the phase of the coloring compound and the developer and the phase of the erasing agent
The separated state is close to the equilibrium state. In this case, the coloring compound
The object and the developer interact with each other to form a color
You. From this state, when the composition system is heated above the melting point,
The coloring agent preferentially dissolves in the elimination agent in the fluid state,
It loses its interaction with the object and becomes decolored. In a molten state
Forcible solidification by quenching certain composition systems
And the quencher takes in more developer than equilibrium solubility
And becomes colorless at room temperature. The amorphous composition system is
Although relatively in a non-equilibrium state, the glass transition point Tg
Longer life at lower temperatures and Tg above room temperature
Then it is not easy to move from the amorphous state to the equilibrium state.
No. Next, as a component of the image forming material of the present invention,
Specific compounds that can be used are described.
As the color-forming compound used in the present invention, leuco-au
Lamins, diaryl phthalides, polyaryl carbs
Knols, acyl auramines, aryl auramines
, Rhodamine B lactams, indolines, spiropi
Electron-donating organic substances such as orchids and fluorans;
It is. [0012]As the coloring compound,Crystal bio
Letlactone (CVL), malachite green lacto
2-anilino-6- (N-cyclohexyl-N-meth
Tylamino) -3-methylfluoran, 2-anilino-
3-methyl-6- (N-methyl-N-propylamino)
Fluoran, 3- [4- (4-phenylaminophenyi)
Ru) aminophenyl] amino-6-methyl-7-chloro
Fluoran, 2-anilino-6- (N-methyl-N-i
Sobutylamino) -3-methylfluoran, 2-anili
No-6- (dibutylamino) -3-methylfluoran,
3-chloro-6- (cyclohexylamino) fluora
2-chloro-6- (diethylamino) fluoran,
7- (N, N-dibenzylamino) -3- (N, N-di
Ethylamino) fluoran, 3,6-bis (diethyla)
Mino) fluoran-γ- (4′-nitroanilino) lac
Tom, 3-diethylaminobenzo [a] -fluoran,
3-diethylamino-6-methyl-7-aminofluora
3-diethylamino-7-xylidinofluoran,
3- (4-diethylamino-2-ethoxyphenyl)-
3- (1-ethyl-2-methylindol-3-yl)
-4-azaphthalide, 3- (4-diethylaminophenyl)
) -3- (1-Ethyl-2-methylindole-3-
Yl) phthalide, 3-diethylamino-7-chloroani
Linofluoran, 3-diethylamino-7,8-benzo
Fluoran, 3,3-bis (1-n-butyl-2-methyl)
Ruindol-3-yl) phthalide, 3,6-dimethyl
Ethoxyfluorane, 3-diethylamino-6-methoxy
C-7-aminofluoran, DEPM, ATP, ETA
C, 2- (2-chloroanilino) -6-dibutylamino
Fluoran, crystal violet carbinol, ma
Rachite green carbinol, N- (2,3-dichloro
Lophenyl) leuco auramine, N-benzoyl aura
Min, Rhodamine B lactam, N-acetyl aurami
, N-phenyl auramine, 2- (phenylimino
Tangylidene) -3,3-dimethylindoline, N,
3,3-trimethylindolinobenzospiropyran,
8'-methoxy-N, 3,3-trimethylindolinove
Nzospiropyran, 3-diethylamino-6-methyl-
7-chlorofluorane, 3-diethylamino-7-metho
Xifluoran, 3-diethylamino-6-benzylo
Xifluorane, 1,2-benzo-6-diethylamino
Fluoran, 3,6-di-p-toluidino-4,5-di
Methylfluoran, phenylhydrazide-γ-lacta
, 3-amino-5-methylfluoranIs mentioned.
These may be used alone or as a mixture of two or more.
Can be. Various colors can be generated by appropriately selecting a coloring compound.
Since the color status can be obtained, multi-color support is possible.
is there. The developer used in the present invention includes
Knol, phenol metal salt, carboxylic acid metal salt, benzo
Phenone, sulfonic acid, sulfonate, phosphoric acid, phosphoric acid
Metal salt, acid phosphate, acid phosphate metal
Salt, phosphorous acid, metal phosphiteIs mentioned.They are
Can be used alone or in combination of two or more
You. The erasing agent used in the present invention is in an amorphous state.
It is desirable that the colorlessness be good when the above-mentioned condition is satisfied. Erase
The more the agent is amorphous and colorless and transparent, the more the image forming material
When the color is erased, the paper can be returned to a state close to the original blank paper.
Wear. Since such properties are required, erasing agents are
Enthalpy change Δ of crystal per weight
A compound with small H and small maximum crystal growth rate MCV
Preferably, there is. Enthalpies of melting of quencher crystals.
If the change ΔH is small, the thermal energy required for melting the crystal
Energy is small, so it is also preferable in terms of energy saving.
No. The melting point of the erasing agent is preferably 50 ° C. or higher.
Erasers have high affinity with color developerspreferable. [0015] [0016]In the present invention, the following two types of erasing agents
Class of compounds are used.That is, (1) melting point and
Glass transition point is relatively high and becomes amorphous at room temperature
Easy-to-use compounds (hereinafter referred to as highly amorphous phase separation control agents)
And (2) the melting point and the glass transition point are relatively low.
It is difficult to become amorphous at normal temperature
But the compatibility with the developer in the fluid state is very high
High compound (hereinafter referred to as low amorphous phase separation inhibitor)
U). One of these two phase separation controlling agents is
The behavior of the image forming material contained is described with reference to FIGS.
Will be explained. In these figures, Tr is room temperature, Tm1 is
The melting point, Tm2, of the low amorphous phase separation controlling agent is
It is the melting point of the phase separation controlling agent. FIG. 1 shows a color-forming compound, a color developer and a highly amorphous substance.
Heating and cooling of the image forming material containing
FIG. 7 is a diagram illustrating a change in image density when the image is rejected. Depart at room temperature
Highly amorphous phase separation controlling agent for color forming image forming material
When heated above the melting point, the developer has a highly amorphous phase separation
Dissolves in control agent and loses interaction with color-forming compound
The color is erased. Cool the imaging material in the molten state
When solidified, the highly amorphous phase separation inhibitor has an equilibrium solubility
Amorphous by taking in more developer than amount
To color. As described above, the highly amorphous phase separation inhibitor is used alone.
Also function as erasing agents. Moreover, highly amorphous phase separation
The control agent tends to become amorphous at room temperature,
Thus, the decolored state can be maintained. However, fluid
If the compatibility with the developer is not so good in the state,
No noticeable change in image density was obtained between the colored state and the decolored state.
May be. FIG. 2 shows a color-forming compound, a color developer and a low amorphous phase.
Heating and cooling of the image forming material containing
FIG. 7 is a diagram illustrating a change in image density when the image is rejected. Depart at room temperature
A low amorphous phase separation controlling agent for an image forming material in a color state.
When heated above the melting point of, a considerable amount of color developer has low amorphous properties
Dissolves in the phase separation control agent, and interacts with the coloring compound.
It loses color and loses color. But the image is in a molten state
Even if the forming material is cooled and solidified, it has low amorphous phase separation
The agent is difficult to become amorphous and may be microcrystallized.
Therefore, the image forming material returns to the original color development state. So low
Amorphous phase separation inhibitors alone function as erasing agents.
Absent. In the present invention, a highly amorphous phase is used as an erasing agent.
Combining a separation control agent with a low amorphous phase separation control agent
Thus, the advantages of both can be utilized. Figure 3 is presented
Color compounds, developers and highly amorphous and low amorphous
And cooling of image forming materials containing neutral phase separation control agent
FIG. 7 is a diagram showing a change in image density when the image is changed. Room temperature (T
In r), a color-forming compound, a color developer and a low amorphous
Phase Separation Inhibitor Mixture Phase and Highly Amorphous Phase Separation Inhibitor
An image is formed in a state where the phase of the agent is separated from the phase. Composition system
Is heated above the melting point (Tm1) of the low amorphous phase separation inhibitor
Then, the color developing agent is a low amorphous phase separation inhibitor in a fluid state.
Dissolves in water and loses its interaction with the coloring compound
I do. In addition, the composition system must be fused with a highly amorphous phase separation inhibitor.
When heated above the point (Tm2), color developer and low amorphousness
Of phase separation inhibitor dissolved in highly amorphous phase separation inhibitor
State. When the composition in the molten state is cooled and solidified,
By the action of the highly amorphous phase separation inhibitor,
Phase Separation Inhibitor Incorporates Above Equilibrium Solubility of Developer
The color is erased at room temperature to make it amorphous. Highly amorphous
Phase-separation inhibitors are highly amorphous,
Suppresses crystallization of phase separation inhibitor and suppresses phase separation of composition system
Control. Therefore, the decolored state of the image forming material
It can be kept stable. [0021]Cyclic sugar alcohol is a highly amorphous phase separation inhibitor
AndD-glucose, D-mannose, D-gas
Lactose, D-fructose, L-sorbose, L-
Rhamnose, L-fucose, D-ribodeose, α-D
-Glucose = pentaacetate, acetoglucose,
Diacetone-D-glucose, D-glucuronic acid, D-
Galacturonic acid, D-glucosamine, D-fructosami
, D-isosugaric acid, vitamin C, erurubic acid,
Haloose, saccharose, maltose, cellobiose,
Gentiobiose, lactose, melibiose, laffy
North, Gentianose, Merezitose, Stachyau
, Methyl = α-glucopyranoside, salicin, amig
Darin and euxanthinic acid. Of these
One or more kinds can be used. [0022]The low amorphous phase separation inhibitor is the cyclic sugar
5- or more-membered ring having a hydroxyl group other than alcohol
Non-aromatic cyclic compounds or other than the above-mentioned cyclic sugar alcohols
Derivatives of cyclic sugar alcohols, typically terpenes
Alcohol. As a low amorphous phase separation inhibitor
Are alicyclic monohydric alcohols (cyclododecanol,
Sahydrosalicylic acid, menthol, isomenthol, ne
Omenthol, neoisomenthol, carbomenthol
, Α-carbomenthol, piperitol, α-terpi
Neol, β-terpineol, γ-terpineol,
1-p-menten-4-ol, isopulegol, dihi
Drocarveol, carveol); alicyclic polyvalent alcohol
(1,4-cyclohexanediol, 1,2-cyclyl)
Rohexanediol, phloroglucitol, quercit
, Inositol, 1,2-cyclododecandio
Quinic acid, 1,4-terpine, 1,8-terpine,
Norhydrate, betulin); polycyclic alcohol derived
Body (Borneol, Isoborneol, Adamantano
Le, norborneol, fencor, camphor, i
Sosorbide); derivatives of cyclic sugar alcohols (1,2:
5,6-diisopropylidene-D-mannitol)
I can do it.In addition, other rings may be added to the above-mentioned cyclic alcohol.
Obtained by reacting a compound having a tertiary structure
When using a material having a molecular structure with large steric hindrance
Improves the temperature stability of the image forming material in the decolored state.
Can beIsosorbide and cyclohexanedica
Esters with rubonic acid are low amorphous phase separation inhibitors
is there.One or more of these can be used
it can. A color-forming compound in the image-forming material of the present invention,
Preferred mixing ratios of the developer and the erasing agent are as follows.
You. The compounding ratio of the color developer is 1 part by weight of the coloring compound.
0.1 to 10 parts by weight, further set to 1 to 2 parts by weight
Is preferred. When the developer is less than 0.1 parts by weight
Indicates image formation by the interaction between a color former and a developer
Insufficient coloring of the material. More than 10 parts by weight of developer
In such cases, it is difficult to sufficiently reduce the interaction between the two.
It will be difficult. The mixing ratio of the erasing agent is 1 part by weight of the coloring compound.
1 to 200 parts by weight, more preferably 10 to 100 parts by weight
It is preferable to set. If the erasing agent is less than 1 part by weight,
The state change between the color forming state and the decoloring state of the image forming material
It becomes difficult to wake up. 200 parts by weight of eraser
If the amount exceeds the above range, the coloring of the image forming material becomes insufficient. The image forming material of the present invention can be used in various forms
can do. For example, a thermal printer
Ink; inkjet printer ink; copy machine
(PPC) and toners such as laser printers;
Printing ink such as clean printing and type printing; ballpoint pen
Can be used as ink for writing utensils such as
Wear. Thermal printer ink is a coloring compound,
Mixing a developer, erasing agent, wax, etc. into plastic
Used by applying to a sheet. Inkjet printer
Ink uses a coloring compound, developer, erasing agent, etc.
It is used by dispersing. The toner is a coloring compound,
Crush compositions containing coloring agents, erasing agents, binders, etc.
It is prepared by In this case, a typical binder
Polystyrene, styrene-acrylic copolymer
Body, polyester, epoxy resin and the like. Picture
The media for forming images is not limited to paper, but overhead
A sheet for a projector or the like may be used. To erase the colored image forming material,
Erasing by heating and melting, and erasing by contact with solvent
There is a way to leave. In the method of erasing by heating, FIG.
The erasure is performed according to the principle described with reference to FIG. image
What is the heating means for erasing the forming material
Is also good. Specifically, a thermal printer head (TP
H), thermal bar, hot stamp, heat roller
Etc. can be used. Also, infrared lamps and hot air
May be heated. In a method in which the image forming material is brought into contact with a solvent,
Is erased according to the following principle. That is, paper
The above color-forming image forming material is brought into contact with a solvent.
And the developer is mixed with a low-amorphous phase-separation inhibitor.
These components are mixed with a highly amorphous phase separation inhibitor
As a result, the interaction between the color developer and the
The imaging material decolorizes. And when the solvent is removed,
Amorphous phase-separation inhibitors develop color beyond parallel solubility
With the agent incorporated, a highly amorphous phase separation inhibitor
The material of the image forming material becomes amorphous.
Fixed. This erase state is very stable at room temperature
It is. The solvent used in this method is (A) a developer and
It must have a property to assist the formation of hydrogen bonds with the quenching agent.
Are preferable, and further, the affinity with the binder (B) is high.
Easily penetrates into the inside of the image forming material
Is preferred. The solvent satisfying the above property (A) is simply
Can be used by Germany. Mix two or more solvents.
In addition, the above two properties may be satisfied. The properties of both the above (A) and (B)
As a solvent having, ether, ketone, ester, etc.
Is mentioned. Specific examples are saturated ethers, such as
Ether, ethyl propyl ether, ethyl isopro
Pill ether, isopentyl methyl ether, butyl ether
Tyl ether, dipropyl ether, diisopropyl ether
-Tel, ethyl isopentyl ether, dibutyl ether
Di, dipentyl ether, diisopentyl ether, di
Hexyl ether; unsaturated ether such as ethyl bi
Nyl ether, allyl ethyl ether, diallyl ether
, Ethyl propargyl ether; dihydric alcohol
For example, 2-methoxyethanol, 2-ethoxy,
Siethanol, 2-butoxyethanol, 1,2-dimethyl
Toxiethane, 1,2-diethoxyethane, 1,2-di
Butoxyethane; cyclic ethers such as oxetane,
Tetrahydrofuran, tetrahydropyran, dioxola
, Dioxane, trioxane; saturated ketones, such as
Acetone, methyl ethyl ketone, methyl propyl keto
, Diethyl ketone, isopropyl methyl ketone,
Methyl ketone, ethyl propyl ketone, isobutyl
Tyl ketone, pinacolone, methyl pentyl ketone, spot
Ethyl ketone, dipropyl ketone, diisopropyl ketone
Ton, hexyl methyl ketone, isohexyl methyl keto
, Heptyl methyl ketone, dibutyl ketone;
Tons, such as ethylideneacetone, allylacetone,
Mesityl oxide; cyclic ketones such as cyclopentane
Non, cyclohexanone, cycloheptanone, cyclo-
Cantanone; esters such as ethyl formate, propyl formate
Butyl, formate, isobutyl formate, pentyl formate, formic acid
Isopentyl, ethyl acetate, isopropyl acetate, acetate acetate
Propyl, butyl acetate, isobutyl acetate, pentyl acetate,
Isopentyl acetate, sec-amyl acetate, hexyl acetate
, Allyl acetate, 2-methoxyethyl acetate, 2-
Ethoxyethyl acetate, 1,2-diacetoxyethane
, Methyl propionate, ethyl propionate, propionate
Propionate, isopropyl propionate, propio
Butyl phosphate, pentyl propionate, isopropionate
Pentyl, sec-amyl propionate, 2-methoxy
Propyl acetate, 2-ethoxypropyl acetate
, Methyl butyrate, ethyl butyrate, propyl butyrate, isobutyrate
Propyl, butyl butyrate, pentyl butyrate, isopench butyrate
Sec-amyl butyrate, methyl isobutyrate, isobutyric acid
Chill, propyl isobutyrate, isopropyl isobutyrate, iso
Butyl butyrate, pentyl isobutyrate, isopench isobutyrate
Sec-amyl isobutyrate, methyl valerate,
Chill, propyl valerate, isopropyl valerate, butyl valerate
Chill, methyl valerate, ethyl valerate, propyl valerate,
Isopropyl valerate, butyl valerate, methyl hexanoate
, Ethyl hexanoate, propyl hexanoate, hexane
And isopropyl acid. Salts other than the above include salts
Methylene chloride, γ-butyrolactone, β-propiolacto
, N-methylpyrrolidinone, dimethylformamide,
Dimethylacetamide, dimethylsulfoxide, etc.
You. These may be used alone or as a mixture of two or more.
You may. When using a mixed solvent, set the mixing ratio arbitrarily
it can. It has the above-mentioned property (A), but has a binder
Solvents having low affinity with, for example, water, methyl alcohol
, Ethyl alcohol, propyl alcohol, isopro
Pill alcohol, butyl alcohol, isobutyl alcohol
, Pentyl alcohol, 2-pentyl alcohol,
3-pentyl alcohol, isopentyl alcohol, 1
-Hexanol, 2-hexanol, 3-hexanol
, Cyclopentanol, cyclohexanol, ethyl
Glycol, propylene glycol, butylene glycol
And glycerin. Although not having the property (A), the binder
Solvents that have a high affinity for
Benzene, propylbenzene, cumene, butylbenze
Isobutylbenzene, sec-butylbenzene, pen
Methylbenzene, diethylbenzene, mesitylene, xy
Len, cresol, ethylphenol, dimethoxyben
Zen, dimethoxytoluene, benzyl alcohol, tri
Lucarbinol, cumyl alcohol, acetophenone,
Propiophenone, hexane, pentane, heptane,
Butane, cyclohexane, cyclopentane, cycloheptane
Tan, cyclooctane, petroleum fractions (petroleum ether, ben
Gin etc.). As mentioned above, the first group of solvents is good alone
Can be used for The second group of solvents can be used alone.
Although it can be used, it may be mixed with a first group of solvents. This place
In both cases, both groups of solvents have the ability to eliminate
It can be used in a mixing ratio. Second group of solvents and third group
When using a mixed solvent with
The mixing ratio of the two is not particularly limited as long as the third group is dissolved.
It is preferable that the amount of the medium is 20 to 80% by weight. Third group
The solvent may be used as a mixture with the first group of solvents. This place
In this case, the solvent of the third group may be 90 wt% or less. Ma
Alternatively, the first to third groups of solvents may be mixed and used.
In this case, the amount of the third group solvent may be set to 80 wt% or less.
preferable. In order to efficiently decolor the image forming material,
The solvent may be pre-heated. In this case, the temperature of the solvent
It is preferred that the temperature be in the range of 40 to 150 ° C. solvent
When using the erasure method by adding an erasure agent to the solvent
Is also good. For example, image formation and
And erase. (1) Color-forming compound, color developing material and highly amorphous
Images are formed with an image forming material containing a quality phase separation inhibitor.
Formed image forming material in the color-developed state
It is erased by contacting with a solvent containing a release inhibitor. (2) Color-forming compound, color developing material, low amorphous property
Image formation with image forming material containing phase separation inhibitor
High-amorphous phase separation
Erase by contact with solvent containing inhibitor. (3) Contains a coloring compound and a color developing material
An image formed with an image forming material
Use high- and low-amorphous phase separation inhibitors
Contact with the contained solvent to erase. [0036] Embodiments of the present invention will be described below. The following fruit
In the embodiment, neutral paper is used as plain paper for forming an image.
00BLATT (manufactured by NEUSIEDLER) was used.
The reflection density of this paper is 0.07. Embodiment 1 Crystal violet lactone as a coloring compound
(CVL) 1 part by weight, propyl gallate 1 as a developer
1 part by weight as a low amorphous phase separation inhibitor
10 parts by weight of ethanol, as a highly amorphous phase separation inhibitor
10 parts by weight of D-glucose, 77 parts by weight as a binder
Part of polystyrene, and LR-14 as a charge control material
7 (Nippon Carlit Co., Ltd.)
And kneaded well. This kneaded material is pulverized by a pulverizer.
As a result, a powder having an average particle size of 10 μm was obtained. This powder 100w
Toner by adding 1 wt% of hydrophobic silica to t%
Was prepared. The obtained toner is used as a copy machine (manufactured by Toshiba,
Merge 38) and put the image on paper
Transferred to Methyl isobutyl on paper with copied image
It was immersed in ketone (MIBK). As a result, copy on paper
The erased image is erased and cannot be confirmed with the naked eye. Extinction
When the reflection density of the paper after leaving was measured, it was 0.08.
Was. The paper from which the image has been erased is heated at 60 ° C. for 300 hours.
Upon leaving, the image did not reappear. That
Later, another image is transferred to the paper from which the image has been erased and erased.
The process was repeated nine times. 10th transfer after that
Image was of the same quality as the first image. further,
Copying and erasing were repeated up to 50 times. as a result,
The paper was physically damaged, but the quality and quality of the copied image
The quality of the erased state was good. Embodiment 2 ODB-2 (manufactured by Yamamoto Kasei) 1 weight as a coloring compound
Part, 2,4,4'-trihydroxybenzo as a developer
1 part by weight of phenone, low amorphous phase separation control agent
1,2,5,6-diisopropylidene-D-mannitol
10 parts by weight of D-phenylene as a highly amorphous phase separation inhibitor
Lactose 10 parts by weight, styrene-me
3 parts by weight of acrylic acid copolymer and 15 parts of paraffin
Parts by weight, knead well using a kneader and heat transfer.
A copying ink was prepared. Apply this ink to a hot melt coater
About 2μ on a 4.5μm thick PET sheet
m to give a thermal transfer sheet. A thermal transfer sheet is placed on paper and
Set on a linter and set the thermal head to 0.15mJ /
When the power of dot is given, characters are printed on the paper from the thermal transfer sheet.
Transfer was stable. 0.
Sentences transcribed when power of 35 mJ / dot or more is given
I was able to erase characters. The paper from which the characters have been erased is heated at 60 ° C. for 300 hours.
Left alone, the letters did not reappear. That
Then, place the thermal transfer sheet on the paper from which
Set on the multi-printer and set 0.15 on the thermal head
When the power of mJ / dot is given, heat transfer sheet to paper
The characters were successfully transferred. Same as above
Thermal transfer and erasing were repeated up to 5 times. Fifth erase
Even afterwards, the characters transferred to the paper can not be seen with the naked eye
Was. However, if you touch the paper surface,
I stopped testing because I knew I was there. Embodiment 3 GREEN-DCF (Hodogaya Chemical)
1) parts by weight, 2,3,4-trihydroxy as a developer
1 part by weight of cibenzophenone, low amorphous phase separation inhibitor
7 parts by weight norborneol, highly amorphous phase separation
5 parts by weight of lactose as inhibitor and wax
And 5 parts by weight of 1-docosanol, and use a kneader.
And kneaded well. After pulverizing this kneaded material, it is put into a mold.
It was pressed and molded to obtain a crayon. Characters were handwritten on paper with the crayons. This
Paper dipped in isopropyl alcohol (IPA)
As a result, handwritten characters are erased and can not be confirmed with the naked eye
Was. When the reflection density of the paper after erasing was measured, it was 0.08.
there were. Leave the paper with the characters erased at 60 ° C for 300 hours
However, the letters did not reappear. Embodiment 4 RED40 (manufactured by Yamamoto Kasei) as a coloring compound, 1 weight
Part, and 2,3,4,4'-tetrahydric as a developer
1 part by weight of roxybenzophenone was added to isoamyl acetate 10
0 parts by weight, melt and add a small amount of anti-drying agent
An ink was prepared. This ink is used in an ink jet printer.
Images were printed on paper in an ink cartridge. one
On the other hand, in 100 parts by weight of IPA, low amorphous phase separation suppression
6 parts by weight of norborneol
Disperse 4 parts by weight of lactose as a phase separation inhibitor
A leaving solvent was prepared. The printed paper is immersed in a solvent for erasing.
As a result, the image was erased and could not be confirmed with the naked eye. The image is
The erased paper was left at 60 ° C for 300 hours.
It did not appear again. Embodiment 5 Crystal violet lactone as a coloring compound
(CVL) 1 part by weight, propyl gallate 1 as a developer
1 part by weight as a low amorphous phase separation inhibitor
Of tancarboxylic acid and 1,4-cyclohexanediol
10 parts by weight of ester, highly amorphous phase separation inhibitor
10 parts by weight of D-glucose, polystyrene as a binder
77 parts by weight of len and 1 part by weight of a charge control agent are mixed,
The mixture was sufficiently kneaded using a kneader. This kneaded material is crushed
To obtain a powder having an average particle diameter of 10 μm. This powder 1
Add 1 wt% of hydrophobic silica powder to 00 wt%
A toner was prepared. The obtained toner is transferred to a toner cart of a copying machine.
The image was transferred to paper by placing it in a ridge. The image is copied
Immersed paper in methyl isobutyl ketone (MIBK)
Was. As a result, the image copied on the paper is erased and
I can no longer confirm. The reflection density of the erased paper was measured.
However, it was 0.08. 60 ° C on the paper with the image erased
For 1000 hours, but the image does not reappear.
won. The low amorphous property used in this embodiment
The phase separation inhibitor is more bulky than that of Example 1.
Due to its molecular structure with large steric hindrance, the temperature in the erased state
The degree stability is better than Example 1. [0051] As described in detail above, the image forming material of the present invention
Image can be easily erased after image formation on paper
And the erased state can be maintained stably.
In this case, the erased paper can be effectively reused.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a change in image density when an image forming material containing a color former, a color developer and a highly amorphous phase separation controlling agent is heated and cooled. . FIG. 2 is a diagram showing a change in image density when an image forming material containing a color former, a color developer, and a low-amorphous phase separation controlling agent is heated and cooled. FIG. 3 shows the change in image density when the image forming material of the present invention containing a color former, a developer, and a highly amorphous and low amorphous phase separation controlling agent is heated and cooled. FIG.

Continuation of the front page (51) Int.Cl. ⁷ identification code FI G03G 7/00 B41M 5/26 D (56) References JP-A-62-280076 (JP, A) JP-A-62-14163 (JP, A JP-A-61-90326 (JP, A) JP-A-60-99695 (JP, A) JP-A-9-169162 (JP, A) JP-A-9-71055 (JP, A) 71052 (JP, A) JP-A-9-20074 (JP, A) JP-A-8-197853 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08 B41M 5 / 00 G03G 7/00

Claims (1)

(57) [Claim 1] In an erasable image forming material containing a color former, a color developer and an erasing agent, the erasing agent
Is, and a cyclic sugar alcohol, other than the cyclic sugar alcohol
5-membered or more non-aromatic cyclic compound having hydroxyl group
Or a cyclic sugar alcohol other than the above cyclic sugar alcohol
An erasable image-forming material comprising a derivative of