JP2007090879A - Recording method, reproducible recording paper, coloring ink, and reproducing method for the recording paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide reproducible recording paper and a reproducing method for the recording paper. <P>SOLUTION: The surface of the recording paper is coated with a water-insoluble or slightly water-soluble resin, and an ink is prevented from soaking into the recording paper. According to this recording method of information, a recording is performed with a colored ink, and the recording paper is reproduced by eliminating the recorded information by washing the recorded paper with water. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recording method, a reproducible recording paper, a colored ink, and a recording paper reproducing method, and more particularly, information recorded on a water-resistant recording paper using a colored ink and unnecessary after use. The recording paper relates to a recording method in which images such as characters on the surface are washed with water, the recording paper is regenerated and reused.

  In recent years, business document creation work and creation of various personal documents are performed by personal computers due to the widespread use of document creation software, and methods of recording (printing) with laser recording devices and inkjet recording devices have become widespread. . Created documents are not only those that need to be saved, but there are many documents that become unnecessary after use, such as after a meeting. Further, when a document is created, it is often recorded for confirmation and correction of the document at the manuscript stage. However, these recorded documents are not required after the confirmation and correction. Therefore, waste of the above paper is pointed out, and from the viewpoints of cost saving and resource saving, the rewritable recording apparatus and copying machine in which a leuco dye and a reversible developer are used in the electrophotographic copying machine system, and the toner has features. Has been proposed.

  However, in the electrophotographic system, toner production requires mixing, kneading, grinding, and classification processes. In particular, in a decolorable toner, the leuco dye and the reversible developer are expensive materials and do not react with each other. It is necessary to manufacture under conditions. Further, special conditions are required to erase the recording with the colored toner, and it is evaluated that normal recording paper can be reused. However, there is a problem from the whole economical point of view.

  The object of the present invention is to use a simple and inexpensive reproducible recording paper and ink, which can be used in general and used information recording equipment, the recording paper can be easily reproduced, and a reproducing apparatus is also added. Investment can be made cheaply, and even if the recording method is based on stationery, it can be erased and reused in the same way, and a recording method, reusable recording paper, colored ink and recording paper corresponding to the social demand for resource saving It is to provide a reproduction method.

  As a result of diligent research to achieve the object of the present invention, the present inventors have used a color ink that forms water-soluble characters and images as a recording agent, and the recording paper is a water-resistant group such as synthetic paper. Use a material whose surface is covered with a water-insoluble or poorly water-soluble resin to prevent ink permeation, and if necessary, the colored ink contains a water-soluble organic solvent and does not repel ink during recording. In this way, characters and images can be recorded, and recorded characters and images can be maintained in a state where they can be read with durability against friction, moisture, etc. in a normal storage state, and become unnecessary. It was found that the information recording sheet can be easily reproduced by washing the characters and images on the surface with water.

  Based on such knowledge, the present inventors use reproducible recording papers, in particular by improving the recording papers that can be used in ink jet recording apparatuses and devising the composition of colored inks that can be used in ink jet recording and stationery. As a result of further studies for the purpose of providing a recording method, the present invention has been completed.

That is, the configuration of the present invention is as follows.
1. In the method of recording information using recording paper and colored ink, the paper is a paper, a synthetic paper or a film whose surface is coated with a water-insoluble or poorly water-soluble resin to prevent the ink from penetrating. The ink is an ink containing a coloring matter and a water-soluble polymer, and after recording information on the paper with the ink, the obtained information recording paper becomes unnecessary, and then the paper is washed with water. An information recording method comprising: erasing recorded information, reproducing a sheet, and recording the information with the ink using the reproduced sheet.

2. 2. The recording method according to 1 above, wherein the ink further contains a water-soluble organic solvent.
3. 2. The recording method according to 1 above, wherein the recording is performed using an ink jet recording apparatus or a writing instrument.
4). 4. The recording method according to 3 above, wherein the ink jet recording apparatus is a piezo method or a thermal method.
5. 4. The recording method according to 3, wherein the writing instrument is a ball point pen, a sign pen, a fiber pen, a fountain pen, a brush pen, or a brush.

6). Recording paper that can be recorded with colored ink and can be reused by washing with water, and the base material of the paper is a polyolefin resin or polyester resin film containing extender pigment and / or white pigment, porous body Synthetic paper or plastic film that has been rendered opaque, or waterproof paper that has been impregnated with water-insoluble or hardly water-soluble resin or wax, and the surface of the base material is coated with water-insoluble or hardly water-soluble resin, and the ink. Reusable recording paper characterized in that permeation is prevented.

7). Contains a dye selected from water-soluble dyes, oil-soluble dyes and pigments, a water-soluble polymer having a group selected from anionic, nonionic and cationic hydrophilic groups, and a water-soluble organic solvent as required. A colored ink characterized in that a recorded image recorded on a recording paper has stickiness on the surface of the recording paper, and the recorded image can be washed with water.

8). 8. A method for reproducing a recording sheet, comprising: removing the recording image recorded on the image recording sheet with water after the recording sheet recorded on the ink described in 7 is no longer needed.

9. An ink jet recording method comprising: recording on a recording paper by an ink jet recording apparatus; and heating and drying the recording paper that has been recorded and wet.
10. An inkjet recording apparatus comprising an apparatus for heating and drying recorded recording paper.

  According to the present invention, a recording apparatus such as an ink jet recording apparatus that has been used in the past is equipped with a recording paper drying device, loaded with a reusable recording paper and colored ink, and recording is performed as usual. The recorded and wet recording paper is dried, and the characters and images of the resulting information recording paper can be stored under normal conditions, and the unnecessary information recording paper can be easily washed with water. Recycled recording paper is an economical, simple, and easy-to-use recording method that can be used in the same way, and can also be applied to stationery in the same way, societal demands for resource saving and cost saving Can be provided.

  As the recording method of the present invention, a conventionally known recording apparatus for recording information can be mentioned. As the recording device, an inkjet recording device, for example, a piezo method or a thermal method is used. Examples of writing instruments include ball point pens, sign pens, fiber pens, fountain pens, brush pens, and brushes that use colored inks that are heavily used in daily life.

  The application of the recording paper of the present invention is used for documents and drawings that do not need to be stored, or drafts of documents. For example, document recording and image recording using an inkjet recording apparatus. For example, using synthetic paper to create personal documents, business documents for office work, tables, graphs, drawings, etc., using a ballpoint pen etc. to create documents or write notes There are ways to use brush writing and calligraphy practice. Synthetic paper and plastic films are not limited to the above-mentioned documents, but are used in various industrial fields such as machinery, construction, civil engineering, electricity, and electronics industries. For example, it can be used for proofreading of design drawings, circuit drawings, and printing plate making in the printing industry.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. First, the reusable recording paper of the present invention will be described.
As the base of the recording paper of the present invention, the quality of the recording paper is deteriorated even when it is immersed in water to recycle the recording paper that is no longer needed after use, or when it is washed with water such as water spray or water flow. Therefore, paper, synthetic paper or film made of a substrate having substantially no water absorption is used. Furthermore, it is difficult for the recording paper to be washed away with water if characters or images recorded with colored ink penetrate into the recording paper. Therefore, the penetration of ink is prevented by coating the surface of the paper with a water-insoluble or hardly water-soluble resin.

  The base material of the recording paper having substantially no water absorption is not particularly limited, and a known base material is used, and it is made of a material that does not discharge harmful substances such as acid gas even when incinerated. A substrate is desirable. In the case of using plastics as a raw material, conventionally known synthetic paper or plastic film can be used. As the synthetic paper, for example, a polyolefin resin such as a polypropylene resin or a polyester resin such as a polyethylene terephthalate resin is used, and it is made opaque by a known method such as adding an extender pigment or a white pigment or making it porous. used. In addition, when paper is used as a raw material, water-insoluble or poorly water-soluble resin or water-resistant paper impregnated with wax by a known method can be used. Since the paper needs to be recorded, written, etc., both need to have a smooth surface and strength.

Examples of the coating resin (polymer) for preventing ink from penetrating the recording paper surface include conventionally known water-insoluble or poorly water-soluble polymers. For example, olefin-based polymers composed of ethylene, propylene, butadiene, isoprene, and the like. (Co) polymer, alkyl (C ₁ -C ₃₀ ) (meth) acrylate, benzyl (meth) acrylate, (meth) acrylic (co) polymer comprising cyclohexyl (meth) acrylate, maleic acid, fumaric acid, (Co) polymers consisting of monobasic (C ₁ -C ₃₀ ) alcohol monoesters and diesters such as itaconic acid, and styrene, vinyltoluene, vinyl acetate, vinyl chloride, etc. Addition polymers such as vinyl (co) polymers; condensation polymers such as polyesters and polyurethanes Melamine resins, such as thermosetting resin such as epoxy resin systems.

The coating made of the above polymer preferably has an affinity for the colored ink. For example, a hydrophilic group such as a carboxyl group, a sulfone group, a hydroxyl group, or a polyalkylene oxide group, (C ₁ -C ₄ ) lower It is preferable to use a polymer having a solvent affinity group such as an ester group.

It is also preferable to use a crosslinkable polymer in order to impart water resistance and strength to the coating. In addition to using the above-mentioned thermosetting resin for forming the coating, it is possible to use a polymer that becomes a water-insoluble coating by reticulation by a heat curing reaction alone or together with a crosslinking agent (reactive comonomer). it can. As the reactive comonomer, conventionally known ones are used. For example, N-methylol acrylamide, N-methoxymethyl acrylamide, glycidyl methacrylate, maleic anhydride, a monomer having a carboxyl group such as the above (meth) acrylic acid is used. And monomers having a hydroxyl group such as hydroxymer (C ₂ -C ₄ ) (meth) acrylate.

  Examples of the cross-linking agent include conventionally known cross-linking agents such as pentaerythritol-polyglycidyl ether, pentaerythritol-hexamethylene diisocyanate adduct, pentaerythritol-tolylene diene according to the reactive group of the cross-linkable polymer. Isocyanates such as isocyanate adducts, carbodiimides such as polyethylene glycol-hexamethylene polyurethane polycarbodiimide, polyglycerol-hexamethylene polyurethane polycarbodiimide, methylol melamines such as tetramethoxymethylol melamine, hexamethoxymethylol melamine, and their initial condensates, etc. Is mentioned.

Examples of the polymer dissolution medium or dispersion medium include known lower (C ₁ -C ₃ ) alcohols, polyhydric alcohols, their alkyl (C ₁ -C ₆ ) monoethers, diethers, and monoether monoacetates. Organic solvents such as esters, ketones, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and water alone or mixed media are used. The coating solution with the above polymer or cross-linking agent added is coated on the surface of the substrate according to a conventional method by a processing method such as coating, printing, dipping, or spraying to form a coating that prevents ink penetration. Is done. The coating amount of the coating solution is preferably about 0.5 to 10 g / m ² in terms of solid content.

  The colored ink used in the present invention contains a coloring matter, a water-soluble polymer, and, if necessary, a water-soluble organic solvent. As representative coloring inks, black ink mainly used for document preparation, cyan, magenta, and yellow three primary color inks for color printing, as well as coloring for color photographic recording, were considered as inks for inkjet recording. Sky blue color, pink color, red color, orange color, green color, violet color ink, and the like. For stationery, black ink for writing, red, blue ink, etc. for color pens for correction, correction, memo, etc., fluorescent yellow, fluorescent pink, fluorescent blue ink for fluorescent pens, etc. Is mentioned.

  The dye used in the preparation of the ink is preferably a dye that is easily dissolved and removed when the recording paper becomes unnecessary after being used and then washed and regenerated. Therefore, durability such as light resistance on the premise of long-term storage is not necessarily required. Therefore, a water-soluble dye is most desirable as a pigment to be used. In view of safety, water-soluble dyes classified as food colorants are preferred. Oil-soluble dyes and pigments are also used in ink compositions that are easily washed with water in combination with a water-soluble polymer. These dyes are used alone or in combination. Examples of water-soluble dyes, oil-soluble dyes and pigments used include conventionally known water-soluble dyes, oil-soluble dyes and pigments described in “Color Index” and the like.

  When selecting a water-soluble dye and a water-soluble polymer, an appropriate combination is made depending on whether the pH of washing water for recycling the recording paper to be used or the ionicity of the added detergent composition is neutral, alkaline or acidic, It is decided. When the composition of the washing water is neutral or alkaline, the hydrophilic group of the water-soluble polymer added to the colored ink is an anionic or nonionic hydrophilic group, and the dye used is an acid dye. And direct dyes. Further, when the composition of the washing water is acidic to neutral, the hydrophilic group of the water-soluble polymer added to the colored ink is a neutral or cationic hydrophilic group, and the dye used is a basic dye. is there.

  As a practically preferred combination, neutral tap water or hot water is used as washing water, and an anionic or nonionic neutral surfactant may be added thereto. As the coloring ink used, an acidic dye or a direct dye, particularly preferably a food coloring, is used, and a coloring ink to which an anionic or nonionic water-soluble polymer is added is preferable.

  The colored ink of the present invention is prepared according to each known composition, physical property, etc. depending on the application. For example, as a colored ink used in an ink jet recording apparatus, each performance is given depending on whether it is a piezo method or a thermal method. Moreover, when used for a writing instrument, it is prepared according to the composition of the colored ink for a ball point pen, a sign pen, a fiber pen, a fountain pen, a brush pen or a brush.

  The content of the pigment in the colored ink has an appropriate concentration by sufficiently satisfying the recording image quality such as color density, saturation and gloss, and satisfying fastness such as drying property and scratch resistance. It is also an important factor to satisfy the viscosity and storage stability as a colored ink. From these points, the content of the pigment is not generally determined by the color developability, but generally 0.3 to 10% by mass, oil-soluble dye or pigment based on the total ink when using a dye. When using, it is preferable that it is 1-20 mass%.

  In addition, by adding a water-soluble polymer to the colored ink, the recording color density of recorded and written characters and images, blurring of drawn lines, discontinuity, non-uniform recording quality, adhesion, and scratch resistance Further, physical properties such as moisture resistance are imparted, and there is an effect that the dye is easily washed when the paper is regenerated with water.

  As the water-soluble polymer, it is preferable to use an alkali-soluble polymer practically in consideration of washing with water after use. The polymer is not particularly limited as long as it is a polymer that is soluble in an alkaline aqueous solution, but the water-soluble group may be a polymer having an anionic property, and may be imparted with a nonionic property or a cationic property. From the standpoint of physical properties such as stickiness and re-solubility, the polymer has a weight average molecular weight of 1,000 to 50,000, preferably a polymer having a molecular weight of 3,000 to 40,000.

Examples of the monomer having an anionic group forming the polymer include α, β-ethylenically unsaturated carboxylic acid such as (meth) acrylic acid, unsaturated dibasic acid such as maleic acid and itaconic acid, and the like. As a monomer having a nonionic group such as a half alkyl (C ₁ -C ₁₈ ) ester thereof, a styrene sulfonic acid, a vinyl sulfonic acid, a sulfate ester of hydroxyalkyl (C ₂ -C ₄ ) (meth) acrylate, or the like. Examples of the monomer having a cationic group such as ethylene glycol ester, polyethylene glycol ester, alkoxy polyethylene glycol ester, glyceryl (meth) acrylate, and the like of the above α, β-ethylenically unsaturated carboxylic acids include dimethylaminoethyl (meta Acrylate, 3- (trimethylammonium chloride) 2-hydroxy - propyl methacrylate, hydrophilic monomers such as vinyl pyridine.

Hydrophobic comonomers that provide film-forming properties to images with the ink include styrene derivatives such as styrene and α-methylstyrene, vinyl naphthalene derivatives, aliphatic (alicyclic), alicyclic and aromatic alcohols of (meth) acrylic acid. Aliphatic, alicyclic and aromatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids such as (C ₁ -C ₃₀ ) esters, alkoxy (C ₁ -C ₄ ) alkyl (C ₂ -C ₄ ) esters And vinyl acetate, butadiene, isoprene, ethylene, propylene, butylene and the like.

  Examples of the polymer include a hydrophilic random copolymer, a hydrophilic graft copolymer, a hydrophilic block copolymer, and the like composed of the hydrophilic monomer mainly composed of the above anionic property and a hydrophobic comonomer. Is mentioned. The copolymerization amount of the anionic monomer depends on the type of anionic hydrophilic group of the monomer and the nature of the other comonomer. It is preferable to set it because it is easy and the trace of recording does not remain on the paper after washing. For example, the amount of copolymerization of the anionic monomer is about 10% by mass to 70% by mass, preferably about 20% by mass to 50% by mass, and the nonionic monomer is about 10% by mass to 30% by mass. When added by mass%, it is about 5% to 40% by mass, preferably about 10% to 30% by mass.

  The alkali used to solubilize this polymer in an aqueous medium is not particularly limited, but considering the effect on odor and skin, for example, alkali metal hydroxide such as sodium hydroxide and potassium hydroxide, ammonia, Primary, secondary or tertiary organic amines, especially when they are handled indoors and have no odor or impact on workers. For example, sodium hydroxide, potassium hydroxide, ammonia, ( Mono-, di-, tri-) ethanolamine and the like are preferred.

  The amount of the water-soluble polymer added to the pigment in the colored ink is an amount that imparts properties such as color developability and sufficient physical properties of the pigment and easy solubility during regeneration, and 5 to 5 for the water-soluble dye. It is preferably 10 to 200% by mass, more preferably 20 to 100% by mass, based on 100% by mass, oil-soluble dye and pigment.

  The colored inks of the present invention include water-based inks and solvent-based inks, and inks containing organic solvents, particularly inks using mixed solvents of water and water-soluble organic solvents as ink media are preferred. When the ink contains a water-soluble organic solvent, the ink is well wetted with respect to the coated surface of the recording paper. Similarly, in the case of a writing instrument, ink is written without being repelled.

It is preferable to use ion exchange water (deionized water) as the water that is the liquid medium of the ink. The water content in the ink is usually 10 to 70% by mass, preferably 20 to 50% by mass. As the water-soluble organic solvent, (C ₁ ~C ₃₎ a lower alcohol, alkylene (C ₂ ~C ₆₎ glycols, polyalkylene (C ₂ ~C ₃₎ glycol, 1,2,6-hexanetriol, glycerin (Mono-tri-) ethylene glycol monoalkyl (C ₁ -C ₄ ) ether, N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like are used. Solvent-based ink media include the above water-soluble organic solvents and alkyl (C ₄ -C ₈ ) alcohols, and the above organic solvents having hydroxyl groups (C ₁ -C ₈ ) ether derivatives, alkyl (C _1- C ₈ ) carboxylic acid ester derivatives and the like are used. These solvents also have functions such as a function of preventing drying of nozzles of ink jet recording apparatuses and pen tips of stationery, and promoting dissolution of dyes.

  In addition to the above components, the colored ink of the present invention may contain other surfactants, antifoaming agents, preservatives and the like other than those described above in order to obtain an ink having desired physical properties as required. Furthermore, urea, thiourea, ethylene urea, or derivatives thereof may be contained as an anti-drying agent for nozzles and nibs.

  The apparatus for heating and drying recording paper wet with the ink of the present invention is installed in an ink jet recording apparatus in-line or off-line. As a heating method, a normal method such as warm air or hot air heating by a heated air blow dryer, infrared drying by an infrared lamp, hot roll heating, dielectric heating or the like is performed.

  As for the recording paper recycling method, the recording paper that has been used and is no longer necessary as described above is immersed in water, sprayed with water, or a stream of water that is recorded or written on the surface of the paper by contact with water, Images are washed away. Moisture on the surface can be directly or squeezed out and wiped off, and then left as it is, dried by blowing with normal temperature or warm air, drying with an infrared dryer, heating with hot rolls, drying with dielectric heating, etc. It is dried and the recording paper is recycled.

Next, the present invention will be described in more detail with specific examples. In the text, “part” and “%” are based on mass unless otherwise specified.
Example 1 (Preparation of recording paper)
A synthetic paper (thickness: 135 μm, basis weight: 89 g / m ² ) using a material obtained by adding calcium sulfite to polypropylene was prepared as a recording paper base material. A maleic acid-modified styrene-ethylene / butylene-styrene triblock copolymer (styrene content: 30%, maleic acid modification: 1.7%) is used as a resin solution for preventing the ink from penetrating the surface of the paper. A 3.3% methyl ethyl ketone / toluene (mass ratio; 40:60) solution (hereinafter referred to as “resin solution 1 for permeation prevention”) was prepared. The synthetic paper was immersed in the penetration preventing resin solution-1, and the resin was applied in an amount of 4 g / m ^{2 in} terms of solid content. It was air-dried at room temperature for 30 minutes, and dried at 80 ° C. for 1 hour to obtain an ink permeation prevention recording paper (referred to as “ink permeation prevention recording paper-1”).

Example 2 (Preparation of aqueous coloring ink)
(A) Synthesis of water-soluble polymer 100 parts of diethylene glycol monobutyl ether and 100 parts of ethanol were added to a reactor equipped with a stirrer, a backflow condenser, a thermometer, a nitrogen introduction tube and a dropping device, and the mixture was heated to 80 ° C. in a hot water bath. Warmed to. In a separate container, 20 parts of styrene, 100 parts of 2-ethylhexyl acrylate, 40 parts of methacrylic acid, 40 parts of dimethylaminoethyl methacrylate and 5 parts of azobisisobutylnitrile (AIBN) are mixed and stirred to prepare a monomer mixture of a uniform solution. did. 1 part of AIBN and 1/3 of the monomer mixed solution were charged into the reaction system, and then the remaining monomer mixed solution was added dropwise over 2 hours while maintaining the temperature at 80 ° C. One part of AIBN was added 1 hour after the completion of the dropwise addition, and polymerization was performed for another 4 hours. After cooling the polymerization solution, an alkaline aqueous solution in which 26.1 parts of potassium hydroxide was dissolved in 73.9 parts of water was added to obtain an acrylic resin solution which was a random copolymer having a solid content of 42.3%. The molecular weight was measured by GPC and was a weight average molecular weight of 15,000 in terms of polystyrene. The resulting resin solution was diluted with water to 40% (hereinafter referred to as “water-soluble polymer-1”).

(B) Preparation of inkjet recording ink C.I. I. Food Black 2 was dissolved in water to a concentration of 10%. 10 parts of water-soluble polymer-1, 10 parts of ethylene glycol, 20 parts of glycerin, 1 part of Surfynol 82 (manufactured by Air Products) and 29 parts of water with respect to 30 parts of the 10% black dye aqueous solution obtained above. After adding 70 parts of the mixed liquid and sufficiently stirring, it was filtered through a membrane filter having a pore size of 5 μm to obtain a black ink for ink jet recording.

  Similarly, C.I. I. Acid Red 249, C.I. I. Direct Blue 199, C.I. I. A 10% aqueous solution of each of Direct Yellow 23 was prepared. In accordance with the method for preparing the black ink for inkjet recording, magenta ink, cyan ink, and yellow ink for inkjet recording were prepared using the respective aqueous dye solutions described above instead of the aqueous black dye solution.

Example 3 (Evaluation of water-based coloring ink)
(A) Each ink obtained in Example 2 (b) is filled in an ink cartridge of a piezo-type ink jet recording apparatus and recorded on the ink permeation-preventing recording paper-1 obtained in Example 1 by the ink jet recording apparatus. Then, it was hot-air dried with a heated blast dryer. Character recording with black ink was clearly recorded and readable, and color recording images were also clearly recorded for each color, and sufficient recording quality was obtained. Also, there was no phenomenon such as transfer to the back of the paper during storage.

(B) Reproduction and reuse of recorded recording paper The recording paper on which the black recording and color image obtained in (a) were recorded was washed with water. The recorded image was easily washed away. The adhering moisture was dried with warm air using a heated air blow dryer, and a completely white recording paper similar to that before use was regenerated. Inkjet recording was again performed on the regenerated recording paper in the same manner as in (a) above. The recording was sufficient, and it was reproduced again by washing with water and drying as described above. This recording-washing was repeated 10 times, but recording-reproduction was sufficiently performed, and there was no problem in recording quality.

Example 4 (Preparation of ball point pen and evaluation of recording paper)
(A) Preparation of ink for ball point pen The black, red, and blue water-based colored inks prepared in Example 2 were filled in a ball point pen ink cartridge loaded with 0.5 mm stainless balls, respectively. Prepared. A sentence was created using a black pen on the blank ink permeation prevention recording sheet 1 obtained in Example 1, and notes, notes, etc. were written using a red and blue pen. In addition, text is added with a black pen to the recording paper on which the document is recorded with the ink jet recording apparatus of Example 3 (a), and red and blue annotations, notes, etc. are entered, and infrared drying is performed with an infrared lamp drying apparatus. did.

(B) Reproduction and reuse of the written recording paper The recording paper on which the black text and the red and blue characters obtained in (a) were written was washed with water. The letters and records were easily washed away. The adhering water was dried with warm air to regenerate completely white recording paper as before use. Writing was again performed on the regenerated recording paper in the same manner as in (a) above. The characters were fully readable and were regenerated again by washing with water and drying with hot air in a heated air dryer as described above. This writing and washing were repeated 10 times, but there was no problem in writing and reproduction.

  In the recording method of the present invention, a coloring ink that forms water-soluble characters or images is used as a recording agent, and the recording paper is coated with a water-insoluble or poorly water-soluble resin on the surface of a water-resistant substrate such as synthetic paper. This prevents ink from penetrating and allows colored ink to contain a water-soluble organic solvent so that it does not repel the ink so that characters and images can be recorded. Or, by drying with a drying device equipped offline, it is durable against friction and moisture, so that it can be maintained in a state where characters, images, etc. can be read in a normal storage state, and it becomes unnecessary after use The recording paper can be easily washed away with tap water or with water using an inexpensive cleaning device. The recording sheet I can be reproduced.

Claims (10)

  In the method of recording information using recording paper and colored ink, the paper is a paper, a synthetic paper or a film whose surface is coated with a water-insoluble or poorly water-soluble resin to prevent the ink from penetrating. The ink is an ink containing a coloring matter and a water-soluble polymer, and after recording information on the paper with the ink, the obtained information recording paper becomes unnecessary, and then the paper is washed with water. An information recording method comprising: erasing recorded information, reproducing a sheet, and recording the information with the ink using the reproduced sheet.   The recording method according to claim 1, wherein the ink further contains a water-soluble organic solvent.   The recording method according to claim 1, wherein the recording is performed using an ink jet recording apparatus or a writing instrument.   The recording method according to claim 3, wherein the ink jet recording apparatus is a piezo method or a thermal method.   The recording method according to claim 3, wherein the writing instrument is a ball point pen, a sign pen, a fiber pen, a fountain pen, a brush pen, or a brush.   Recording paper that can be recorded with colored ink and can be reused by washing with water, and the base material of the paper is a polyolefin resin or polyester resin film containing extender pigment and / or white pigment, porous body Synthetic paper or plastic film that has been rendered opaque, or waterproof paper that has been impregnated with water-insoluble or hardly water-soluble resin or wax, and the surface of the base material is coated with water-insoluble or hardly water-soluble resin, and the ink. Reusable recording paper characterized in that permeation is prevented.   Contains a dye selected from water-soluble dyes, oil-soluble dyes and pigments, a water-soluble polymer having a group selected from anionic, nonionic and cationic hydrophilic groups, and a water-soluble organic solvent as required. A colored ink characterized in that a recorded image recorded on a recording paper has stickiness on the surface of the recording paper, and the recorded image can be washed with water.   A method for regenerating a recording sheet, comprising: removing an image recorded on the image recording sheet with water after the recording sheet according to claim 6 recorded with the ink according to claim 7 becomes unnecessary.   An ink jet recording method comprising: recording on a recording paper by an ink jet recording apparatus; and heating and drying the recording paper that has been recorded and wet.   An inkjet recording apparatus comprising an apparatus for heating and drying recorded recording paper.