JPH07257017A - Image forming method and recording medium - Google Patents

Abstract

PURPOSE:To enhance fixing properties, a character grade, image density and the uniformity of a solid image by forming a recording medium by adding a water-soluble dye, a monomeric substance having ionicity opposite to that of the water soluble dye and having a mol.wt. of a predetermined value or less and a polymeric substance having a mol.wt. of a predetermined value or more. CONSTITUTION:Ink containing at least a water-soluble dye having an anionic group or a water-soluble dye having a cationic group is applied to a recording medium 25 through a head 13 to form an image. The recording medium 25 in this case contains at least a monomeric substance with a mol.wt. of 1000 or less having ionicity opposite to that of the water-soluble dye and a polymeric substance with a mol.wt. of 2000 or more. As the substance with the mol.wt. of 1000 or less, a monomeric cationic org. compd., for example, laurylamine is used and, as the substance with the mol.wt. of 2000 or more, polyacrylamide being a nonionic water-soluble polymer is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to plain paper without special coating, coated paper with coating,
The present invention relates to a recording medium such as a recording sheet having a base material such as a plastic sheet coated, and particularly to a recording medium suitable for an inkjet recording system. Further, the present invention relates to an image forming method mainly using an inkjet recording system using these recording media.

[0002]

2. Description of the Related Art Inkjet recording systems have been attracting attention because they can easily achieve high-speed recording, colorization, and high-density recording, and recording apparatuses using the inkjet recording system have also become widespread. As a recording paper applied to such an ink jet recording system, a dedicated coated paper as disclosed in, for example, JP-A-59-35977 and JP-A-1-135682 has been used. These dedicated coated paper type recording papers are suitable for forming high-definition and clear images, but have the following five problems. 1. Apply to a texture like plain paper. 2. Writability with a pencil is poor. 3. The powder in the coat layer may fall off. 4. It is not versatile (when used in other recording methods, it may not have sufficient recording suitability). 5. The cost may be higher than plain paper.

Further, in the field of monochrome recording and business color recording, it is possible to record on a low-priced and versatile medium (paper) that can be easily obtained at the office, instead of using a dedicated paper according to the recording method. It has been demanded.

However, a so-called plain paper type recording medium which is currently popular in offices is disclosed in, for example, Japanese Patent Laid-Open No.
No. 1-132244, JP-A-59-162561, JP-A-59-191068, which is a toner transfer paper (PPC paper) for a copying machine or the like using an electrophotographic method, and is a sufficient ink jet recording. No suitable one has been found.

There are the following five problems when the above PPC paper is applied to an ink jet recording system. 1. The ink absorbency is poor, and when a large amount of ink is applied, the drying and fixing of the ink is slow. (Ink is not fixed,
If an object touches the recording surface in an undried state, the formed image may be damaged. ) 2. When the ink is absorbed into the paper layer, it bleeds along the fibers that make up the paper, resulting in excessive bleeding of the dots, jagged edges around the dots, and blurring. No image can be obtained. 3. When trying to obtain a color image, the inks of multiple colors are stacked one after another before fixing on the paper,
At the boundary between different-color images, colors are blurred or mixed nonuniformly (hereinafter, this phenomenon is called bleeding), and a satisfactory image cannot be obtained. 4. The water resistance of the recorded image is insufficient because a water-soluble recording agent is used. 5. The coloring property of the coloring agent in the paper is insufficient.

In order to address these problems, for example, as means for increasing the water resistance of recorded images, Japanese Patent Laid-Open No. 56-996 has been proposed.
No. 93 discloses an inkjet recording paper containing a halogenated quaternary ammonium salt or the like.
However, such a water-resistant inkjet recording paper has a drawback that the light resistance of a recording material (dye or the like) is remarkably reduced. Further, as means for improving water resistance and light resistance, JP-A-61-58788 discloses a recording paper containing a polyallylamine salt. However, a recording paper containing only a polyallylamine salt without providing a special coat layer has a problem that the image density is low and bleeding easily occurs.

On the other hand, in the ink jet recording system, the application of a recording medium other than the above-mentioned paper has been studied and is being put into practical use. For example, a recording sheet having a porous ink absorbing layer on a substrate and a recording sheet having an ink receiving layer made of a water-soluble or hydrophilic polymer on a transparent substrate have been used. JP-A-60-220750 discloses a polyester film having a saponification degree of 70 to 90.
A recording sheet provided with a hydrophilic coating consisting of mol% of water-soluble polyvinyl alcohol is disclosed.

However, high-speed recording, colorization,
Along with the improvement and spread of the performance of ink jet recording apparatuses such as high density, recording sheets other than paper using a plastic substrate as described above are required to have high-level and wide-ranging characteristics. That is, in order to obtain a high resolution and high quality recorded image, 1. Abundant ink absorption and quick ink drying and fixing. 2. When ink dots are adjacent to each other, the adjacent ink dots should not flow into each other's ink dots and mix unevenly to prevent bleeding. 3. 3. No beading (dye does not agglomerate on the ink absorption layer to form a bead-like shape and uneven density). The applied ink droplets should not spread on the recording sheet and the diameter of the ink dots should not become excessively large. 5. The image density of ink dots is high, and blurring does not occur around characters and images. 6. The coloring component of the ink is excellent in color development. 7. Good color reproducibility and high-definition images can be obtained. 8. It has excellent water resistance. Ink jet recording characteristics similar to those of the above-mentioned paper are required.

Among these characteristics, water resistance is an important characteristic as in the case of the above-mentioned paper. In contrast,
Japanese Unexamined Patent Publication No. 1-190483 discloses an ink jet recording sheet with improved water resistance of a recorded image. In such a recording sheet, ink fixability, image density, degree of image bleeding, water resistance, etc. The other ink jet recording characteristics have not reached a satisfactory level.

[0010]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention has as its problems the following: (1) good character and good character quality when forming a recorded image. . (2) Sufficient image density is obtained and the solid image is highly uniform. Also, (3) bleeding does not occur during color image formation. (4) Color reproducibility is good and high-definition images can be obtained. (5) Make the recorded image completely waterproof. It is an object of the present invention to provide a recording medium that sufficiently satisfies the above requirements, particularly the above requirements when applied to an inkjet recording method, and an image forming method using the recording medium.

A further object of the present invention is the above-described recording medium, which has a texture like plain paper and is applied to various recording systems such as an electrophotographic recording system, a thermal transfer system, an impact system and an inkjet recording system. Even if a recording image that satisfies the above requirements and has excellent performance can be obtained in common, and that it can be used as a writing sheet such as a pencil, felt-tip pen, and ballpoint pen, and an image forming method using the same. That is.

Still another object of the present invention is to provide a recording sheet which is a recording medium satisfying the above requirements and which uses a base material other than paper, and an image forming method using the same.

[0013]

The above-mentioned problems can be solved by the present invention described below.

That is, the present invention relates to an image forming method for forming an image by applying an ink containing a water-soluble dye having at least an anionic group or a water-soluble dye having a cationic group to a recording medium to form an image. The medium has a molecular weight of 1000, which has an ionicity opposite to that of the water-soluble dye.
An image forming method comprising at least the following substances and a polymer substance having a molecular weight of 2000 or more.

The present invention is also a recording medium containing at least a cationic substance having a molecular weight of 1000 or less and a polymer substance having a molecular weight of 2000 or more.

In a preferred embodiment of the present invention, the recording medium comprises the cationic substance and the polymeric substance,
A recording paper obtained by impregnating a sheet material made of a fibrous substance and a filler, a recording paper obtained by applying the cationic substance and the polymer substance to the surface of a sheet made of a fibrous substance and a filler, or the cationic substance. And a recording sheet comprising the polymer substance applied to the surface of a plastic substrate or other substrate other than paper to form an ink absorbing layer.

Further, the present invention is directed to the above recording medium.
An image forming method is characterized in that a recorded image is formed by applying an ink containing a water-soluble dye having at least an anionic group.

The operation and effect of the present invention will be described in detail below.

When an ink containing a dye having an anionic group is applied to the recording medium of the present invention, a cationic substance having a molecular weight of 1000 or less and a polymeric substance having a molecular weight of 2000 or more, which are constituent components of the recording medium. And ink
Mix on the recording medium or at a position where it penetrates into the recording medium. As a result, a low molecular weight cationic substance (molecular weight of 1000 or less) contained in the recording medium as the first step of the reaction.
Then, the dye contained in the ink, for example, a dye having an anionic group, causes association due to ionic interaction and instantaneously separates from the solution phase.

Then, in the second step of the reaction, the above-mentioned dye-low molecular weight cationic substance association product is adsorbed by a high molecular weight substance having a molecular weight of 2000 or more contained in the recording medium to form a dye produced by the association. The size of the aggregates becomes even larger.

As a result, when the recording medium is a recording paper, the dye aggregates are less likely to enter the gaps between the fibers constituting the recording medium, or are less likely to move in the coating layer, and only the liquid portion which is solid-liquid separated. Will penetrate into the recording paper or the coating layer, so that both print quality and fixability can be achieved. Further, when the recording medium is a recording sheet having an ink absorbing layer provided on a plastic substrate, the dye aggregates are less likely to move in the ink absorbing layer, and similarly, only the liquid portion obtained by solid-liquid separation is the ink. Since it penetrates into the absorption layer, both print quality and fixability are achieved.

At the same time, the low molecular weight cationic substance, the anionic dye and the molecular weight 2 produced by the mechanism as described above are used.
The agglomerates formed with more than 000 polymer substances have a very high viscosity and do not move with the movement of the liquid medium, so that adjacent dots may have different colors as in the case of full-color image formation described above. Even if formed, they do not mix with each other and bleeding does not occur. Further, the above-mentioned aggregates are essentially water-insoluble, and the water resistance of the formed image is perfect. Furthermore,
The light fastness of the recorded image formed by the shielding effect of the polymer substance forming the aggregate is also improved.

In addition to the above, according to the present invention, it is not necessary to use a cationic polymer substance or a polyvalent metal salt as in the prior art, or even if it is necessary to use it, in order to further improve the effect of the present invention. Since it is only necessary to use it as an auxiliary, it is possible to minimize the amount used. As a result, the deterioration of the color developability of the dye, which has been a problem when a large amount of a cationic polymer substance or a polyvalent metal salt is used to obtain a water resistance effect, is eliminated.

Next, the components in the recording medium of the present invention will be described in more detail.

When printing is performed on the recording medium of the present invention using an ink containing a water-soluble dye having an anionic group, (a) a low molecular weight cationic substance having a molecular weight of 1,000 or less, and (b) a molecular weight as essential constituents. It contains 2000 or more polymer substances.

As described above, the low molecular weight cationic substance which is the component (a) is ionic between the dye used in the recording image formation, preferably the water-soluble dye having an anionic group. It functions to form an aggregate by interaction. The formation reaction rate of this aggregate needs to be extremely high.

Specific examples of the low molecular weight cationic substance having a molecular weight of 1000 or less of the component (a) include primary to secondary to tertiary amine salt type compounds, specifically laurylamine, coconut amine and stearyl. Hydrochlorides such as amines and rosinamines, acetates and the like; quaternary ammonium salt type compounds, specifically lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltributylammonium chloride,
Benzalkonium chloride, etc .; Pyridinium salt-type compound, specifically cetylpyridinium chloride, cetylpyridinium bromide, etc .; Imidazoline-type cationic compound, specifically 2-heptadecyl-hydroxyethylimidazoline, etc .; Ethylene oxide adduct of higher alkylamine Specifically, organic compounds such as dihydroxyethylstearylamine are preferred examples.

Further, in the present invention, an amphoteric surfactant having a cationic property in a certain pH range can be used as the low molecular weight cationic substance which is the component (a). Specific examples thereof include amino acid type amphoteric surfactants; R-NH-C.
H ₂ —CH ₂ —COOH type compounds; betaine type compounds, specifically carboxylic acid salt type amphoteric surfactants such as stearyl dimethyl betaine, lauryl dihydroxyethyl betaine; sulfuric acid ester type, sulfonic acid type compounds, Examples include amphoteric surfactants such as phosphoric acid ester type. When these amphoteric surfactants are used, the mixing ratio of the raw materials of the recording medium is adjusted so that the pH is below their isoelectric point, or the isoelectric point is adjusted when mixed with ink on the recording medium. It is necessary to take one of the methods of adjusting the pH to a point below the point.

The examples of the low molecular weight cationic substance compounds having a molecular weight of 1,000 or less have been described above, but the compounds usable in the present invention are not necessarily limited to these. In the present invention, among the above-mentioned cationic substances having a low molecular weight, those having a molecular weight of 100 to 700 have a surface-active ability, react quickly with a dye, and improve the edge sharpness of an image. Particularly preferred.

As described above, the polymer substance having a molecular weight of 2000 or more, which is the component (b) of the recording medium of the present invention, contains, as described above, the association of the dye in the ink and the low molecular weight cationic substance in the molecule. Solid-liquid separation is achieved by further increasing the size of the aggregates of dyes generated by adsorption and association, and making them difficult to enter or move into other components of the recording medium (the gaps between the paper fibers and the ink absorption layer). It functions to achieve both print quality and fixability by impregnating only the liquid portion soaked into the recording medium.

Specific examples of the polymer substance as the component (b) include polyacrylic amide which is a nonionic water-soluble polymer; polyvinylpyrrolidone; water-soluble cellulose such as carboxymethyl cellulose hydroxymethyl cellulose and hydroxypropyl cellulose. Examples thereof include polyvinyl methyl ether, polyvinyl acetal, polyvinyl alcohol, and the like, but are not limited thereto. When the molecular weight of these polymer substances is 2000 or more, the effect is sufficient when the present invention is carried out, but a more preferable polymer substance has a molecular weight of 2000 to 100.
00. It is more preferable to use a high molecular weight substance having a molecular weight within this range because the image density on the recording medium is increased.

As the polymer substance as the component (b), a cationic polymer substance can be preferably used. When a cationic polymer substance is used, bleeding resistance and water resistance are further improved.

Specific examples of such a cationic polymer substance include, but are not limited to, polyallylamine hydrochloride, polyaminesulfone hydrochloride, polyvinylamine hydrochloride, and chitoate acetate. .
Further, the compound is not limited to the hydrochloride type acetate type compound.

In addition to the above, as the cationic polymer substance, a substance obtained by cationizing a part of the above-mentioned nonionic polymer substance can be used. Specific examples thereof include a copolymer of vinylpyrrolidone and a quaternary salt of aminoalkyl acrylate, and a copolymer of quaternary salt of acrylic amide and aminomethyl acrylic amide.
Of course, it is not limited to these compounds.

Further, the polymer substance and the cationic polymer substance used in the above-mentioned component (b) are satisfactory if they are water-soluble, but may be a dispersion such as latex or emulsion.

Next, other components that may be contained in the recording medium of the present invention will be described in detail.

The recording medium of the present invention contains the above-mentioned component (a).
In addition to (b) and (b), a surfactant other than the cationic substance may be added. By adding a surfactant, the image density is increased and the occurrence of bleeding is further suppressed depending on the ink used for image formation. Specific examples of such a surfactant include higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, higher alkylamine ethylene oxide adducts, fatty acid amide ethylenes. Oxide adduct, ethylene oxide adduct of fats and oils, polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, alkanol Examples thereof include fatty acid amides of amines, but are not necessarily limited thereto. Among these, acetylene alcohol, acetylene glycol and ethylene oxide adducts thereof are particularly effective.

In the recording medium of the present invention, when the components (a) and (b) are applied to the surface of a base material made of a sheet material made of a fibrous substance and a filler, plastic, etc., the components ( It is also possible to incorporate components having a binder effect on a) and (b). Such components are not limited as long as they exhibit solubility or affinity for so-called aqueous ink, and specific examples include polyvinyl alcohol, polyurethane,
Polyester, polyacrylic acid (ester), polyvinylpyrrolidone, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose,
Synthetic resins such as carboxymethyl cellulose, polyethylene oxide, polyacetal resin, melamine resin or modified products thereof, albimine, gelatin,
Examples thereof include natural resins such as casein, starch, cationized starch, gum arabic and sodium alginate. These compounds can be used alone or in the form of a mixture of two or more kinds.

In the recording medium of the present invention, if necessary, p
Additives such as H-adjusting agents, preservatives and antioxidants may be added.

Next, various aspects of the recording medium of the present invention will be described.

One aspect of the recording medium of the present invention is the above-mentioned essential component (a) a low molecular weight cationic substance having a molecular weight of 1000 or less, and (b) in a sheet containing general pulp fibers or filler or on the surface thereof. It is a recording paper containing a polymer having a molecular weight of 2000 or more.

Compared with the conventional neutral PPC paper, such recording paper does not undergo any major changes in surface shape and physical characteristics other than recording characteristics, maintains the texture of plain paper, and is a toner transfer for electrophotographic recording. It is applicable to both paper and inkjet recording paper. With such recording paper,
In addition to the effects due to the components (a) and (b) and the combination with a specific recording liquid being exhibited, it has the texture of plain paper as described above and can be used with a pencil. It is excellent in writing properties, and even when a coating layer is provided, powder falling is reduced.

Such a recording paper is preferably obtained by impregnating the cationic substance (component (a)) and the polymeric substance (component (b)) into a sheet material composed of a fibrous substance and a filler. Alternatively, the above-mentioned cationic substance and the above-mentioned polymer substance are applied to the surface of a sheet material comprising a fibrous substance and a filler.

When one embodiment of the present invention is the recording paper type as described above, the amounts of the components (a) and (b) can be appropriately set according to the kind of the compound used for each component. The total amount of the two components is preferably in the range of 0.05 to 7 g / m ² . When it is less than 0.05 g / m ² ,
There is a possibility that the effects of both components as described above may not be sufficiently obtained, while if it exceeds 7 g / m ² , the ink absorption of the recording paper may deteriorate, bleeding may not be improved, and light resistance may be impaired. is there. Amount of the component ((a) and (b)
The most preferable range of 0.3 to 5 g / m ²
In this range, the suppression of bleeding and the light resistance are particularly improved, and the image density is also significantly improved.

The weight ratio of components (a) and (b) is preferably 100: 1 to 1:20. If the amount of the component (a) is larger than that in the case of 100: 1, the water resistance may be insufficient, and if the amount of the component (b) is larger than that in the case of 1:20, the image density is low and the bleeding is bleeding. May be insufficiently suppressed. The most preferred ratio of components (a) and (b) is 5: 1 to 1:20 (weight ratio).

The recording paper is mainly composed of chemical pulp represented by LBKP, NBKP, etc., a size (inner surface size, surface size) agent, and a filler, and other papermaking auxiliaries, if necessary, and prepared by a conventional method. To be done.

As the pulp material, in addition to chemical pulp, mechanical pulp or recycled pulp of waste paper may be used in combination, or the main component thereof may be used.

Examples of the sizing agent (inner surface sizing agent) include rosin size, alkyl ketene dimer, alkenyl succinic anhydride, petroleum resin type size, epichlorohydrin and acrylamide.

As the filler, for example, calcium carbonate,
Examples include kaolin, talc, titanium dioxide and the like.

Examples of the surface sizing agent (or coating agent) include casein, starch, cellulose derivatives such as carboxymethyl cellulose and hydroxymethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate, polyacrylamide, etc., and swelling ink. Hydrophilic resin, SBR latex, acrylic emulsion, styrene / acrylic acid copolymer and other resins having hydrophilic and hydrophobic moieties in the molecule, silicone oil, paraffin, wax, fluorine compounds, etc. Examples of the substance include the sizing agent and the like.

In the recording paper of the present invention, the pH value for water extraction is adjusted to preferably 6 or more, more preferably 7 or more. The water extraction pH is a value obtained by measuring the pH of the extract when about 1.0 g of the test piece specified in JIS-P-8133 is immersed in 70 ml of distilled water according to JIS-Z-8802. If the pH value is less than the above range, the long-term storage property of the recording paper itself may be impaired, and the dye may not exhibit sufficient color developability on the paper surface.

The Steckigt sizing degree of the recording paper of the present invention is preferably in the range of 0 to 40 seconds. If the Steckigt sizing degree is excessively high, it takes a long time for the recording liquid to be absorbed in the paper layer, and thus the fixing property and the drying property of the adhered ink may be deteriorated. It is preferable to set.

The recording paper of the present invention is made from the above-mentioned raw materials, but preferably in the form of a sheet containing a fibrous substance such as pulp and a filler, the low molecular weight cationic substance of the component (a). And the polymer substance of the component (b) are blended in an appropriate amount. For blending these components (a) and (b), preferably, a method of impregnating a sheet material composed of a fibrous substance and a filler and a method of coating the surface of the sheet material can be appropriately adopted.

The recording paper of the present invention finally has a basis weight of 50 to 1
It is preferably in the range of 50 g / m ² . 50 g / m
^If it is less than ² , strike-through and cockling are likely to occur.
If it exceeds 0 g / m ² , the transportability may deteriorate.

In the present invention, in order to further improve the resolution and the like of the recorded image on the recording paper as described above,
In addition to the cationic substance (component (a)), the polymer substance (component (b)), and optionally other additive components, a sheet material composed of a fibrous substance and a filler,
It is also possible to appropriately mix pigments that are commonly used.

In this case, in order to maintain the texture of the plain paper, the surface of the recording paper is in a state in which the fibrous substance forming the sheet material is covered with pigment particles and the fibrous substance is partially exposed. Is preferred. In particular,
A sheet obtained by impregnating a sheet material composed of a fibrous substance and a filler with the cationic substance, the polymer substance and a pigment in an appropriate amount by a method as described below, or by coating the surface thereof. The recording paper is preferably characterized in that the fibrous substance is covered with pigment particles, and the fibrous substance is partially exposed on the surface thereof.

As the above pigment, an inorganic pigment or an organic pigment can be used in combination. Examples of inorganic pigments include, but are not limited to, silica, alumina, aluminum silicate, magnesium silicate, hydrotalcite, calcium carbonate, titanium oxide, clay, talc, basic magnesium carbonate and the like. Not a thing.
Examples of the organic pigment include, but are not limited to, urea resin, urea formalin resin, polyethylene resin, polystyrene resin, and other plastic pigments.

Incidentally, these pigments are, for example, 0.
1-5 g / m ² is applied.

In order to prepare a recording paper containing the above-mentioned pigment, an aqueous coating liquid containing the cationic substance, the polymer substance, a binder and other additives in addition to the pigment is prepared and the coating liquid is prepared. The working solution is applied or impregnated onto the surface of the sheet material composed of the fibrous substance and the filler by a known method, for example, a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a size press method, a shimsizer method, etc. . After that, it is dried using a hot air drying oven, a heating drum, etc. to obtain a recording paper having a desired surface shape. Furthermore, in order to smooth the surface or improve the strength of the surface, a super calendar treatment may be applied.

Another embodiment of the present invention is the above-mentioned essential component (a) a low molecular weight cationic substance having a molecular weight of 1000 or less, and (b) a polymeric substance having a molecular weight of 2000 or more, and, if necessary, the above-mentioned binder and interface. The recording sheet is characterized in that an ink absorbing layer is formed by applying other components such as an activator to the surface of a substrate other than paper such as a plastic film.

With respect to such a recording sheet, the action and effect resulting from the above components (a) and (b) and the combination with a specific ink are also exhibited, and the ink jet recording suitability is particularly excellent.

When one embodiment of the present invention is the recording sheet as described above, the amount of the ink absorbing layer, that is, the coating amount, is preferably 0.2 to 50 g / m 2 as a total amount on one side of the plastic substrate. ² , particularly preferably 1 to 30 g / m
It is within the range of ² . If it is less than 0.2 g / m ² , the ink absorbency is insufficient and the adhered ink may not be dried or bleeding may occur. If it exceeds 50 g / m ² , curling or peeling of the coating layer may occur. May occur. When the coating amount is converted to thickness, it is 0.05
It is preferably in the range of ˜100 μm.

In this case, the weight ratio of components (a) and (b) is preferably 20: 1 to 1:20. 20:
When the amount of the component (a) is larger than that in the case of 1, the image bleeding may occur under high temperature and high humidity, and the sharpness of the image may become constant, and in the case of 1:20, the amount of the component (b) may be increased. If there are many,
Image sharpness may be deteriorated due to a decrease in image density or occurrence of bleeding.

The amounts of the components (a) and (b) in the ink absorbing layer can be appropriately set according to the kind of the compound used for each component, but the total amount of the two components is 0. It is preferably in the range of 005 to 70% by weight. If it is less than 0.005% by weight, the effects of both components as described above may not be sufficiently obtained, while if it exceeds 70% by weight, the light resistance may be impaired. The most preferable range of the component amount (the total amount of (a) and (b)) is 0.01 to 30% by weight in the ink absorbing layer.

In the recording sheet, a filler similar to the pigment used in the recording paper can be added to the ink absorbing layer in order to improve blocking, transportability and the like.

Examples of such fillers are silica, alumina, aluminum silicate, magnesium silicate, basic magnesium carbonate, talc, clay, hydrotalcite, calcium carbonate, titanium oxide, zinc oxide, polyethylene, polystyrene and poly. Examples thereof include plastic pigments such as acrylates, but are not limited thereto.

In addition, additives such as various dispersants, fluorescent colorants, pH adjusters, preservatives, antioxidants, penetrants, waterproofing agents, defoamers, ultraviolet absorbers, viscosity modifiers, plasticizers, etc. Can also be blended. These additives can be appropriately selected and used from known compounds according to the purpose.

In the recording sheet, examples of the plastic material used as the substrate include polyethylene terephthalate, diacetate, triacetate, cellophane, celluloid, polycarbonate, polyimide, polyvinyl chloride, polyvinylidene chloride, polyacrylate, polyethylene, polypropylene and the like. Is mentioned. These plastic materials can be appropriately selected and used according to various purposes such as the purpose of use of the recording medium, the use of images, and the adhesiveness with the composition forming the ink absorbing layer.

In order to prepare the recording sheet as described above, a coating solution containing the above-mentioned cationic substance, the above-mentioned polymer substance, a binder and other additives is prepared, and the coating liquid is prepared by a known method. For example, it is applied to the surface of the substrate by a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a bar coater, a spray coat method, a slit coat method, a gravure coater method, a curtain coater method or the like. After that, hot air drying oven,
It is dried using a heating drum or the like to obtain a desired recording sheet.

In still another embodiment of the present invention, the above-mentioned essential components (a) a low molecular weight cationic substance having a molecular weight of 1,000 or less, (b) a high molecular weight substance having a molecular weight of 2,000 or more, and, if necessary, the binder described above. Another example is a recording sheet in which other components such as a surfactant are applied to the surface of a smooth plate material such as a glass plate by the same method as in the case of using a plastic substrate to form an ink absorbing layer.

In the case of a recording medium having an ink absorbing layer provided on a substrate such as a plastic film or a glass plate as described above, the total basis weight is preferably 50 to 5000 g.
/ M ² range.

Next, the image forming method of the present invention will be described in detail.

The image forming method of the present invention is most characteristic in using the recording medium as described above, but it is preferable to use an ink containing a water-soluble dye having an anionic group. The ink includes a water-soluble dye containing this anionic group, and generally water, a water-soluble organic solvent, and if necessary, for example, a viscosity adjusting agent, a pH adjusting agent, a preservative, a surfactant, an oxidizing agent. Contains an inhibitor.

The water-soluble dye containing an anionic group used in the present invention includes a color index (COLOU).
R INDEX), water-soluble acid dyes,
There is no particular limitation as long as it is a direct dye or a reactive dye. Further, even those not described in the color index are not particularly limited as long as they have an anionic group such as a sulfone group or a carboxyl group. The water-soluble dyes referred to herein also include those having solubility dependence on pH.

Specific examples of the water-soluble organic solvent used in the ink include amides such as dimethylformamide and dimethylacetamide; ketones such as acetone; ethers such as tetrahydrofuran and dioxane; polyethers such as polyethylene glycol and polypropylene glycol. Alkylene glycols; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol and other alkylene glycols; ethylene glycol methyl ether, diethylene glycol monomethyl ether, Lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether; ethanol, isopropyl alcohol n- butyl alcohol, monohydric alcohols such as isobutyl alcohol; In addition, glycerin, N- methyl-2-pyrrolidone, 1,3-dimethyl -
Examples thereof include imidazolidinone, triethanolamine, sulfolane, dimethylsulfoxide and the like. The content of the water-soluble organic solvent in the ink is not particularly limited, but is 1 to 50% by weight, more preferably 2 to 30% by weight.
Is a preferable range.

In addition to these, additives such as a viscosity adjusting agent, a pH adjusting agent, an antiseptic, an amphoteric surfactant, an antioxidant, and an evaporation accelerator may be added, if necessary. The choice of surfactant is especially important in adjusting the permeability of the liquid.

The preferred physical properties of the ink are as follows at around 25 ° C. First, pH is 3 to 12, surface tension is 10 to 60 dyn / cm, and more preferably 10
-40 dyn / cm, viscosity is 1-30 cps.

In order to further enhance the effects of the present invention, an anionic surfactant or an anionic polymer substance may be added to the ink, in addition to the components described above. Alternatively, the amphoteric surfactant may be adjusted to a pH above its isoelectric point before use. As such anionic surfactants, for example, general ones such as carboxylate type, sulfate type, sulfonate type and phosphate type can be used without problems. Further, examples of the anionic polymer include alkali-soluble resins, specifically, sodium polyacrylate, and those obtained by copolymerizing acrylic acid with a part of the polymer. It is not limited to.

As the specific examples of the image forming method of the present invention, an ink containing a water-soluble dye having an anionic group has been described above. It can also be applied to the case where a water-soluble dye having a cationic group is used.

In this case, the recording medium has a molecular weight of 1
The same effect can be achieved by using at least an anionic substance having a molecular weight of 000 or less and a polymer substance having a molecular weight of 2000 or more, preferably an anionic polymer substance.

An example of the anionic substance is an anionic surfactant. For example, carboxylate type, sulfate type, sulfonate type, phosphate type and the like can be used.

Further, as an example of the anionic polymer substance,
Examples thereof include alkali-soluble resins, specifically, sodium polyacrylate, and those obtained by copolymerizing a part of polymer with acrylic acid.

The image forming method of the present invention can be applied to general recording systems, but is particularly suitable for ink jet recording systems. Such an inkjet recording method can be applied to any of the conventionally known inkjet recording methods in which droplets of ink (recording liquid) are ejected from nozzles to perform recording by using various driving principles. is there. As a typical example, in the method described in Japanese Patent Application Laid-Open No. 54-59936, the ink subjected to the action of thermal energy undergoes a rapid volume change, and the action force due to this state change ejects the ink from the nozzle. An inkjet method can be used.

An example of an ink jet recording apparatus suitable for the ink jet recording method according to the present invention will be described with reference to the drawings. An example of the head configuration, which is the main part of the apparatus, is shown in FIGS. 1, 2 and 3.

FIG. 1 is a sectional view of the head 13 taken along the ink flow path, and FIG. 2 is a sectional view taken along the line AB of FIG.

In these figures, the head 13 is made of glass, ceramics or a plastic plate having a groove 14 for passing ink, and a heating head 15 used for heat-sensitive recording.
(The head is shown in the figure, but not limited to this). Fever head 15
Is a protective film 16 formed of silicon oxide, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 formed of nichrome, a heat storage layer 19, and a substrate 20 having a good heat dissipation property such as alumina. There is.

The ink 21 has a discharge orifice (fine hole) 2
2, the meniscus 23 is formed by the pressure P.

When an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact with the area, and the meniscus is generated by the pressure. 23 is ejected, the ink 21 is ejected,
The recording droplet 2 becomes the recording droplet 24 from the orifice 22, and the recording sheet 2
Fly toward 5.

FIG. 3 is a perspective view showing the appearance of a multi-head in which a large number of the heads shown in FIG. 1 are arranged in parallel. The multi-head is formed by closely adhering a glass plate 27 having a multi-groove 26 and a heating head 28 similar to that described in FIG.

FIG. 4 shows an example of the overall structure of an ink jet recording apparatus incorporating such a head. In the figure, reference numeral 61 denotes a blade as a wiping member, one end of which is held by a blade holding member to become a fixed end, which is in the form of a cantilever. The blade 61 is arranged at a position adjacent to the recording area by the recording head, and
In the case of this example, the recording head is held in a protruding form in the moving path of the recording head. Reference numeral 62 denotes a cap, which is disposed at a home position adjacent to the blade 61, and has a configuration in which it moves in a direction perpendicular to the moving direction of the recording head and contacts the ejection port surface to perform capping. Further, 63 is an ink absorber provided adjacent to the blade 61.
Similarly to the above, the recording head is held in a protruding form in the moving path of the recording head. The blade 61, the cap 62, the absorber 63
The ejection recovery unit 64 is constituted by the blade 61 and the absorber 63, and water, dust, etc. are removed from the ink ejection port surface.

Reference numeral 65 denotes a recording head having ejection energy generating means for ejecting ink to a recording medium facing the ejection port surface where ejection ports are arranged for recording, and 66 a recording head 65 having the recording head 65 mounted thereon. It is a carriage for moving the. The carriage 66 slidably engages with the guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and its adjacent area.

Reference numeral 51 designates a paper feed section for inserting a recording medium, and 5
A paper feed roller 2 is driven by a motor (not shown). With these configurations, the recording medium is fed to the position facing the ejection opening surface of the recording head, and is ejected with the ejection roller 53 arranged as the recording progresses.

In the apparatus having the above-described structure, when the recording head 65 returns to the home position after recording is completed, the cap 62 of the head recovery section 64 is retracted from the movement path of the recording head 65, but the blade 61 is moved. It projects inside. As a result, the ejection port surface of the recording head 65 is wiped. When the cap 62 contacts the protruding surface of the recording head 65 for capping, the cap 62
Moves so as to project into the moving path of the recording head.

When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are at the same positions as the above wiping positions. As a result, the ejection opening surface of the recording head 65 is wiped even during this movement.

The movement of the recording head to the home position as described above is performed not only at the end of recording or at the time of ejection recovery, but also at a predetermined interval while the recording head moves in the recording area for recording. Is moved to a home position adjacent to, and the wiping is performed in accordance with this movement.

When performing color recording, four recording heads containing black, cyan, magenta, and yellow inks are arranged in parallel on the carriage 66.
Further, one recording head may be divided into four columns in a row without arranging the recording heads in parallel. The ink is not 4 colors,
Three colors of cyan, magenta and yellow may be used.

[0097]

EXAMPLES The present invention will be described in more detail below with reference to examples. These examples are described for the purpose of facilitating the understanding of the present invention, and do not limit the present invention in particular.

[Example 1] * Production of recording paper 90 parts of LBKP and 10 parts of NBKP as raw material pulp were mixed and beaten, and then kaolin (made by Tsuchiya Kaolin) 10
Parts, 0.2 parts of alkenyl succinic anhydride and 5 parts of cationized starch were blended to prepare a recording base paper (P-1) having a basis weight of 70 g / m ² and a Steckigt sizing degree of 23 seconds by a conventional method.

This base paper was impregnated with a solution (M-1) prepared by mixing and dissolving the following components, removing excess water and drying in an oven at 120 ° C. for 1 minute to obtain a recording paper. At this time, the amount of the solution applied to the base paper is 2.5 g /
It was set to m ² .

(Composition of M-1): The total amount is 100. -Cationic compound benzyltributylammonium chloride; 1.5 parts (Brand name: BTBAC, Sanyo Kasei) -Polymer compound polyacrylamide; 0.05 parts (Brand name: Sanfloc N-500P, Sanyo Kasei) -Water The rest

* Preparation of ink A liquid having a pore size of 0.22 μm was prepared by mixing the following components.
Yellow, magenta, cyan, and black inks (1) -Y, (1)-by pressure filtration with a membrane filter (trade name; Fluoropore filter, manufactured by Sumitomo Electric Industries, Ltd.)
M, (1) -C, and (1) -K were obtained. The total amount is 100
Adjust to. (1) -Y C.I. I. Direct Yellow 86 (dye); 2 parts thiodiglycol; 10 parts acetylenol EH; 0.05 parts water; balance (1) -M I. Acid Red-289; Same composition as (1) -Y except that 2.5 parts was used. (1) -C dye was used as C.I. I. Acid Bull-9: Same composition as (1) -Y except that 2.5 parts was used. (1) -K dye was used as C.I. I. Food Black-2: Same composition as (1) -Y except that 3 parts were used.

* Formation of image Using the recording paper and ink obtained as described above,
A color image is formed (printed) on a recording paper by a recording device equipped with an ink jet type recording head which has recording nozzles at a rate of 14 per 1 mm and ejects ink droplets by the action of heat. Was evaluated. Each evaluation was performed by the following method.

1. Image density A solid image with a duty of 100% was formed with black ink, and after standing for 12 hours, the reflection densitometer was measured with a reflection densitometer Macbeth RD918 (manufactured by Macbeth).

2. Bleeding Solid areas of 100%, 200%, and 300% duty were printed adjacently, and the degree of bleeding at the boundary of each color was visually observed. Bleeding was rated as ○ when there were practically no problems, and X was rated at other levels.

3. Water resistance A drop of water was dropped on a character of 100% duty with a dropper, and the sample was naturally dried and visually evaluated. The case where the image flow did not occur, but the character was thickened, was marked with ◯. In particular, ⊚ means that no image flow and no thickening of characters occur. Other levels were marked as x.

The results are shown in Table 1 below.

Example 2 10 parts of starch was further added to the solution M-1 to mix and dissolve it, and the thickened liquid was applied to the base paper P-1 with a bar coater at 1.5 g / m ² for recording. Got the paper. Subsequently, the same ink as in Example 1 was used for the recording paper, and image formation and recording image evaluation were performed in the same method and conditions.

The results are shown in Table 1.

[Example 3] The base paper P-1 was impregnated with a solution M-2 prepared by mixing and dissolving the following components, removing excess water, and dried in an oven at 120 ° C for 1 minute, and recorded. Got the paper. At this time, the amount of the solution applied to the base paper was set to 2.5 g / m ² .

(Composition of M-2): The total amount is adjusted to 100. -Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, Sanyo Kasei) -Polymer compound polyacrylamide; 0.05 parts (trade name: Sanfloc N-500P, Sanyo Kasei) -Interface Activator Acetylene glycol-EO adduct: 0.5 part (trade name; acetylenol EH, manufactured by Kawaken Fine Chemicals) ・ Water; balance

Image formation and recording image evaluation were performed on the recording paper according to the same method and conditions as in Example 1.

The results are shown in Table 1.

Example 4 10 parts of starch was further added to the solution M-2, mixed and dissolved, and the thickened liquid was applied to the base paper P-1 by a bar coater at a rate of 1.5 g / m ² to make a recording paper. Got Subsequently, the same ink as in Example 1 was used for the recording paper, and image formation and recording image evaluation were performed in the same method and conditions.

[Examples 5 to 13] Next, using the components shown in Table 2 below, liquids having the compositions shown in Table 3 below were prepared, and the above-mentioned base paper P-1 was prepared in exactly the same manner as in Example 1. An impregnated recording paper was obtained (the amount of liquid applied to the base paper was 2.5 g /
m ² ). Further, the ink having the formulation shown in Table 3 was used for the recording paper, and image formation and evaluation of the recorded image were performed by the same method and conditions as in Example 1. However, the same components as in Example 1 were included except for the components listed in Table 3 of the ink used. Further, the amounts of water in the liquid and the ink are adjusted so that the total sum of the constituent components is 100.

[Comparative Example 1] The base paper P-1 (solution M-1)
The same ink as in Example 1 is used for
Printing and evaluation were performed by the same method and conditions.

The results are shown in Table 1.

[Comparative Example 2] The base paper P-1 was impregnated with a liquid consisting only of the polymer compound obtained by removing the cationic compound from the solution M-1 and water (the amount of the liquid applied to the base paper was 2.5 g. / M ² ), the same ink as in Example 1 was used, and printing and evaluation were performed by the same method and conditions.

The results are shown in Table 1.

As is clear from Table 1, Examples 1 to 13
As a result, an image having good image density, bleeding, and water resistance was obtained, whereas in Comparative Examples 1 and 2, only images having poor bleeding were obtained at low density, and the water resistance of the image was also poor. .

Further, all of the recording papers of Examples 1 to 13 had the texture of plain paper and were excellent in the writing ability with a pencil, and especially powders of Examples 2 and 4 did not fall off.

[0121]

[Table 1]

[0122]

[Table 2]

[0123]

[Table 3]

Example 14 Production of Recording Paper 90 parts of LBKP and 10 parts of NBKP as raw material pulp were mixed and beaten, and then kaolin (made by Tsuchiya Kaolin) 10
Parts, 0.2 parts of alkenyl succinic anhydride, and 0.3 parts of cationized starch, and a basis weight of 72 g / m ^{2 according} to a conventional method.
A recording base paper (P-2) having a Steckigt size degree of 10 seconds was produced.

The base paper was coated with a solution (M-3) prepared by mixing and dissolving the following components with a bar coater so that the dry coating amount was 2 g / m ² , followed by drying to give a recording paper. Obtained.

(Composition of M-3) Finely divided silica (trade name; Cycilia 470, manufactured by Fuji Silysia); 7 parts Polyvinyl alcohol (trade name; Gohsenol NL-)
06, Nippon Synthetic Chemical Industry Co., Ltd.); 7 parts. Cationic compound benzyltributylammonium chloride; 7 parts (trade name; BTBAC, Sanyo Kasei Co., Ltd.). Polymer compound polyacrylamide; 0.3 parts (trade name; Sunfloc N-). 500P, manufactured by Sanyo Kasei Co., Ltd.) Water; 79 parts Subsequently, using the recording paper obtained as described above, a recorded image is formed (printed) by the same ink and method and conditions as in Example 1, and recorded. The images were evaluated for the following items by the following methods and standards.

1. Image Density (Similar to Example 1) A 100% duty solid image was formed with black ink, and the reflection densitometer after standing for 12 hours was measured with a reflection densitometer Macbeth RD918 (manufactured by Macbeth).

2. Bleeding Black, yellow, magenta, cyan, blue, green, and red solid portions were printed adjacent to each other, and the degree of bleeding at the boundary portion of each color was visually observed. The boundary is recognizable as a straight line ◎, the boundary is clear but slightly lacking linearity is ◯, the ink is mixed and the boundary cannot be determined is ×, and the middle one is Δ. .

3. Water resistance (similar to Example 1) A drop of water was dropped on a character of 100% duty with a dropper to allow it to naturally dry and visually evaluated. The case where the image flow did not occur, but the character was thickened, was marked with ◯. In particular, ⊚ means that no image flow and no thickening of characters occur. Other levels were marked as x.

4. Lightfastness A solid image of magenta is printed, and as a test to accelerate the evaluation of the lightfastness of the printed matter, the printed matter is irradiated with xenon lamp light for 30 hours using an Atlas Fade Meter Ci-35. The ratio with the image density of was calculated.
The larger the ratio, the better the light resistance.

The results are shown in Table 4 below.

Example 15 A solution M-4 prepared by mixing and dissolving the following components was applied to the above-mentioned base paper P-2 by a bar coater so that the dry coating amount was 2 g / m ² . It was then dried to obtain a recording paper.

Subsequently, the same ink as in Example 14 was used for the recording paper, and image formation and evaluation of the recorded image were performed by the same method and conditions.

The results are shown in Table 4.

(Composition of M-4) Finely divided silica (trade name; Cycilia 470, manufactured by Fuji Silysia); 7 parts Polyvinyl alcohol (trade name; Gohsenol NL-)
06, manufactured by Nippon Synthetic Chemical Industry); 7 parts ・ Cationic compound benzyltributylammonium chloride; 5.3 parts (trade name; BTBAC, manufactured by Sanyo Kasei) ・ Polymer compound: polyacrylamide; 0.3 parts (trade name; Sunflock) N-500P, Sanyo Kasei) ・ Surfactant acetylene glycol-EO adduct; 0.5 part (trade name; acetylenol EH, Kawaken Fine Chemicals) ・ Water; 79 parts

[Examples 16 to 24] The base paper P-2 was prepared as follows.
A solution MX prepared by mixing and dissolving the following components was coated with a bar coater so that the dry coating amount was 3 g / m ^2, and then dried to obtain a recording paper.

In the solution MX, the water resistant component is
The compounds shown in Table 2 were used to make the compositions shown in Table 5.

Subsequently, on the recording paper, using the inks having the formulations shown in Table 5, the image formation and the evaluation of the recorded image were performed by the same method and conditions as in Example 14. However, except for the components shown in Table 5 of the ink used,
It contains the same ingredients as used in Example 1. Further, the amounts of water in the solution and the ink composition are adjusted so that the total of the constituent components is 100 parts.

The results are shown in Table 4.

(Composition of MX) Finely divided silica (trade name; Sicilia 470, manufactured by Fuji Silysia); 10 parts Polyvinyl alcohol (trade name; Gohsenol NL-)
06, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.); 7 parts.

[Comparative Example 3] The base paper P-2 (solution M-3)
The same ink as in Example 14 was used for (not impregnating) and printing and evaluation were performed by the same method and conditions.

The results are shown in Table 4.

[Comparative Example 4] The base paper P-2 was impregnated with a liquid consisting only of a polymer compound obtained by removing the cationic compound from the solution M-3 and water (the amount of the liquid applied to the base paper was 2 g / m 2. ² ) and the same ink as in Example 14 was used, and printing and evaluation were performed in the same manner and under the same conditions.

[Comparative Example 5] As a water resistant component of MX,
Polyallylamine hydrochloride (trade name; PAA-HCl-1
Example 14 (16) except that a solution was prepared using only 7 parts of 0 L, a molecular weight of 100,000, manufactured by Nitto Boseki, and the solution was used.
Recording paper was prepared in the same manner as in (1) to (24), and printing and evaluation were performed using the same ink and the same method and conditions.

The results of Comparative Examples 3 to 5 are shown in Table 4 together.

As is clear from the results of Table 4, Example 1
4 to 24, images with good image density, bleeding, and water resistance were obtained, whereas in Comparative Examples 3 and 4, only images with low bleeding and bad bleeding were obtained,
Moreover, the water resistance of the image was inferior. In Comparative Example 5, the water resistance was excellent, but the image density, bleeding, and light resistance were slightly inferior.

The surface condition of the recording papers of Examples 14 to 24 was observed with a scanning electron microscope.
Within the range of m ² , one or more pulp fibers with a shape with a length of 100 μm or more are recognized as fibers, and the fibers are covered with pigment (silica), and the fibers placed on the surface are partially It was exposed.

However, when the surface condition of the recording paper of Comparative Example 3 was observed, the entire surface was covered with pulp fibers.

[0149]

[Table 4]

[0150]

[Table 5]

Example 25 * Production of recording sheet Polyethylene terephthalate film (thickness 100 μm
m; Lumirror, manufactured by Toray), a solution (M-5) prepared by mixing and dissolving the following components was coated with a bar coater to a coating thickness of 10 μm, and then in an oven at 120 ° C. for 3 minutes. It was dried to obtain a recording sheet.

(Composition of M-5) -Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei) -Polymer compound (cationic compound) cationized polyvinyl alcohol; 10 parts ( Product name CM
-318, Kuraray) ・ Water; balance

Subsequently, using the recording sheet obtained as described above, a recording image is formed (printed) with the same ink and method and conditions as in Example 1, and the recording image is recorded by the following method for the following items. And was evaluated according to the standard.

1. Image density A solid image with 100% duty was formed with black ink, and the transmission density after standing for 12 hours was measured by a transmission densitometer Macbeth TR524 (manufactured by Macbeth Co.).

2. Bleeding 100%, 200%, and 300% duty solid areas are printed adjacent to each other, and the degree of bleeding at the boundary of each color is projected by a transmissive projector M4000 (manufactured by Sumitomo 3M Ltd.) Was visually evaluated. Bleeding was rated as ○ when there were practically no problems, and X was rated at other levels.

3. Storing bleeding Characters are printed with magenta on the solid part of 100% duty of yellow and put in a transparent middle bag for file binder (Clear Pocket CL-303, manufactured by Lion). 3
After storing in an environment of 0 ° C./80% for 10 days, the image was projected by a transmissive projector M4000 (manufactured by Sumitomo 3M Ltd.), and the quality of the projected characters was evaluated. Characters that do not flow and have no character weight are ◎, those that have no character flow but have character weight are ○, those with a higher character weight level than the level of ○ are △, and other grades are It was set to x.

The results are shown in Table 6.

Examples 26 to 41 A coating solution prepared by mixing and dissolving the following components in the above-mentioned polyethylene terephthalate film (thickness 100 μm; Lumirror, manufactured by Toray) was applied so that the coating thickness becomes 10 μm. After coating with a coater, it was dried in an oven at 120 ° C. for 3 minutes to obtain a recording sheet.

Subsequently, the same ink as in Example 25 was used for each recording sheet, and image formation and recording image evaluation were carried out under the same method and conditions.

The results are shown in Table 6 (to Example 32) and Table 7 (Examples 33 to 41).

(Composition of coating liquid of Example 26) Cationized polyvinyl alcohol; 10 parts (trade name C
M-318, manufactured by Kuraray) -Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei) -Polymer compound (cationic compound) polyallylamine hydrochloride (trade name PAA-HCl 3)
L, manufactured by Nittobo); 0.1 part ・ Water; balance

(Composition of coating liquid of Example 27) Cationized polyvinyl alcohol; 10 parts (trade name C
M-318, manufactured by Kuraray) -Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei) -Polymer compound (cationic compound) polyallylamine hydrochloride (trade name PAA-HCl 3)
L, Nitto Bo); 0.1 part ・ Surfactant acetylene glycol-EO adduct; 0.5 part (trade name; acetylenol EH, Kawaken Fine Chemicals) ・ Water; balance

(Composition of coating liquid of Example 28) Polyvinyl alcohol (trade name 217, manufactured by Kuraray);
10 parts-Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei) -Polymer compound (cationic compound) Polyallylamine hydrochloride (trade name PAA-HCl 3
L, manufactured by Nittobo); 0.1 part ・ Water; balance

(Composition of coating liquid of Example 29) Polyvinyl alcohol (trade name 217, manufactured by Kuraray);
10 parts-Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei) -Polymer compound (cationic compound) Polyallylamine hydrochloride (trade name PAA-HCl 3
L, Nitto Bo); 0.1 part ・ Surfactant acetylene glycol-EO adduct; 0.5 part (trade name; acetylenol EH, Kawaken Fine Chemicals) ・ Water; balance

(Composition of coating liquid of Example 30) Polyvinylpyrrolidone (trade name K-120, GAF)
Made); 10 parts; cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei); polymer compound (cationic compound) polyallylamine hydrochloride (trade name PAA-HCl 3)
L, manufactured by Nittobo); 0.1 part ・ Water; balance

(Composition of coating liquid of Example 31) Polyvinylpyrrolidone (trade name K-120, GAF)
Made); 10 parts; cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei); polymer compound (cationic compound) polyallylamine hydrochloride (trade name PAA-HCl 3)
L, Nitto Bo); 0.1 part ・ Surfactant acetylene glycol-EO adduct; 0.5 part (trade name; acetylenol EH, Kawaken Fine Chemicals) ・ Water; balance

(Coating liquid composition of Example 32) Polyvinyl acetal (trade name KW-1, manufactured by Sekisui Chemical Co., Ltd.); 10 parts Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, Sanyo) Chemical conversion) -Polymer compound (cationic compound) Polyallylamine hydrochloride (trade name PAA-HCl 3
L, manufactured by Nittobo); 0.1 part ・ Water; balance

(Coating liquid composition of Example 33) Polyvinyl acetal (trade name KW-1, manufactured by Sekisui Chemical Co., Ltd.): 10 parts Cationic compound benzyltributylammonium chloride: 1.5 parts (trade name: BTBAC, Sanyo) Chemical conversion) -Polymer compound (cationic compound) Polyallylamine hydrochloride (trade name PAA-HCl 3
L, Nitto Bo); 0.1 part ・ Surfactant acetylene glycol-EO adduct; 0.5 part (trade name; acetylenol EH, Kawaken Fine Chemicals) ・ Water; balance

(Composition of coating liquid of Example 34) Cationized polyvinyl alcohol (trade name; CM-3)
18, Kuraray); 10 parts Cationic compound benzyltributylammonium chloride; 1.5 parts (Brand name: BTBAC, Sanyo Kasei) Polymer compound (cationic compound) Polyamine sulfone (Brand name PAS-92, Nitto) Spinning); 0.1 part ・ Water; Remainder

(Composition of coating liquid of Example 35) Cationized polyvinyl alcohol (trade name; CM-3)
18, Kuraray); 10 parts Cationic compound benzalkonium chloride (trade name; G-50, Sanyo Chemical Co., Ltd.); 1.5 parts Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-92) , Nitto Boseki); 0.1 part ・ Water; Remainder

(Composition of coating liquid of Example 36) Cationized polyvinyl alcohol (trade name; CM-3)
18, manufactured by Kuraray); 10 parts; cationic compound, benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei); polymer compound (cationic compound) polyamine sulfone (trade name PAS-120, Nitto) Spinning); 0.1 part ・ Water; Remainder

(Composition of coating liquid of Example 37) Cationized polyvinyl alcohol (trade name; CM-3)
18, Kuraray); 10 parts Cationic compound benzalkonium chloride (trade name; G-50, Sanyo Kasei Co., Ltd.); 1.5 parts Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-120) , Nitto Boseki); 0.1 part ・ Water; Remainder

(Composition of coating liquid of Example 38) Polyvinyl alcohol (trade name: 217, manufactured by Kuraray); 10 parts Cationic compound benzyltributylammonium chloride: 1.5 parts (trade name: BTBAC, manufactured by Sanyo Kasei Co., Ltd.) ) -Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-92, manufactured by Nitto Boseki); 0.1 part-Water; balance

(Coating liquid composition of Example 39) Polyvinyl alcohol (trade name: 217, manufactured by Kuraray); 10 parts Cationic compound benzalkonium chloride (trade name: G-50, manufactured by Sanyo Kasei); 1 .5 part-Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-92, manufactured by Nitto Boseki); 0.1 part-Water; balance

(Composition of coating liquid of Example 40) Polyvinyl alcohol (trade name; 217, manufactured by Kuraray); 10 parts Cationic compound benzyltributylammonium chloride; 1.5 parts (trade name; BTBAC, manufactured by Sanyo Kasei Co., Ltd.) ) -Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-120, manufactured by Nitto Boseki); 0.1 part-Water; balance

(Composition of coating liquid of Example 41) Polyvinyl alcohol (trade name; 217, manufactured by Kuraray); 10 parts Cationic compound benzalkonium chloride (trade name; G-50, manufactured by Sanyo Kasei); 1 .5 parts-Polymer compound (cationic compound) Polyamine sulfone (trade name PAS-120, manufactured by Nitto Boseki); 0.1 part-Water; balance

[Example 42] An anionic surfactant: sodium lauryl sulfate (trade name Emal D:
A recording sheet was prepared, an image was formed, and an evaluation was performed by using the same materials, methods and conditions as in Example 25, except that 1.0 part of Kao) was added and used. The results are shown in Table 7.

Example 43 A recording sheet was prepared, an image was formed and evaluated using the same materials, methods and conditions as in Example 25, except that an acrylic plate was used as the base material. The results are shown in Table 7.

Example 44 A recording sheet was prepared, an image was formed and evaluated by using the same materials, methods and conditions as in Example 28 except that an acrylic plate was used as the base material. The results are shown in Table 7.

Comparative Examples 6 to 8 A coating solution prepared by mixing and dissolving the following components in the above-mentioned polyethylene terephthalate film (thickness 100 μm; Lumirror, manufactured by Toray) was applied so that the coating thickness becomes 10 μm. After coating with a coater, it was dried in an oven at 120 ° C. for 3 minutes to obtain a recording sheet.

Subsequently, the same ink as in Example 25 was used for each recording sheet, and image formation and recording image evaluation were carried out under the same method and conditions. The results are shown in Table 6.

(Composition of coating liquid of Comparative Example 6) Cationized polyvinyl alcohol (trade name; CM-3)
18, made by Kuraray); 10 parts ・ Water; balance

(Composition of coating liquid of Comparative Example 7) -Polyvinyl alcohol (trade name: 217, manufactured by Kuraray); 10 parts-Water: balance

(Composition of coating liquid of Comparative Example 8) Polyvinyl alcohol (trade name: 217, manufactured by Kuraray); 10 parts Cationic compound Polyallylamine hydrochloride (trade name: PAA-HCL 3)
L, molecular weight 10,000, manufactured by Nitto Boseki); 1.5 parts water; balance

Reference Example 1 Polyethylene terephthalate film described above (thickness 100 μm; Lumirror, manufactured by Toh)
After coating a coating solution prepared by mixing and dissolving the following components with a bar coater to a coating thickness of 10 μm,
It was dried in an oven at 120 ° C for 3 minutes to obtain a recording sheet.

Subsequently, the same recording liquid as in Example 25 was used for each recording sheet, and image formation and recording image evaluation were performed by the same method and conditions. The results are shown in Table 6.

(Composition of coating liquid of Reference Example 1) Polyvinyl alcohol (trade name; 217, manufactured by Kuraray); 10 parts Cationic compound benzyltributylammonium chloride (trade name;
BTBAC, manufactured by Sanyo Kasei); 1.5 parts ・ Water; balance

As is clear from the results of Tables 6 and 7,
Image density, bleeding,
Images with good storage bleeding were obtained, whereas in Comparative Examples 6 and 7, only images with low density and poor bleeding were obtained, and storage bleeding of images was also inferior. In Reference Example 1, the bleeding was good, but the storage bleeding was slightly inferior. In Comparative Example 8, the storage bleeding was excellent, but the image density was insufficient and bleeding occurred.

[0189]

[Table 6]

[0190]

[Table 7]

[0191]

As described in detail above, according to the present invention,
Ink fixability, sufficient image density can be obtained, bleeding does not occur particularly during color image formation, and excellent color reproducibility and high-definition images can be obtained, and water resistance of the obtained recorded image is improved. An excellent recording medium and an image forming method using the same are provided. The present invention is particularly suitable for color ink jet recording.

Particularly, the recording paper based on the sheet material composed of the fibrous substance and the filler has the same texture as the plain paper,
Pencil writing is good and there is no worry of powder falling. Further, it can be used not only as an inkjet paper, but also as a general-purpose paper such as a toner transfer paper for electrophotographic recording.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a head portion of an example of an inkjet recording device.

FIG. 2 is a cross-sectional view of a head portion of an example of an inkjet recording device.

FIG. 3 is an external perspective view of a head portion of an example of an inkjet recording apparatus.

FIG. 4 is a perspective view showing an example of an inkjet recording apparatus.

[Explanation of symbols]

 13 head 14 groove 15 heat generating head 16 protective film 17-1, 17-2 electrode 18 heat generating resistor layer 19 heat storage layer 20 substrate 21 ink 22 orifice 23 meniscus 24 recording droplet 25 recording sheet 26 multi-groove 27 glass plate 28 heating head 51 Paper Feed Section 52 Paper Feed Roller 53 Paper Ejection Roller 61 Wiping Member 62 Cap 63 Ink Absorber 64 Ejection Recovery Section 65 Recording Head 66 Carriage 67 Guide Axis 68 Motor 69 Belt

Front page continued (72) Inventor Akio Kashiwazaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kenichi Moriya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Yuko Nishioka, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Masato Katayama 3-30-2, Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Invention Yutaka Kurabayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Katsuhiko Takahashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (31)

[Claims] 1. An image forming method for forming an image by applying an ink containing a water-soluble dye having at least an anionic group or a water-soluble dye having a cationic group to a recording medium to form an image. An image forming method comprising at least a substance having a molecular weight of 1,000 or less and a polymer substance having a molecular weight of 2000 or more, which has an ionic property opposite to that of the water-soluble dye. 2. A recording medium containing at least a cationic substance having a molecular weight of 1000 or less and a polymer substance having a molecular weight of 2000 or more. 3. The recording medium according to claim 2, wherein the cationic substance having a molecular weight of 1,000 or less is an organic compound. 4. The high molecular substance has a molecular weight of 2000 or more 1
The recording medium according to claim 2, which is a polymer substance having a molecular weight of 0000 or less. 5. The recording medium according to claim 2, wherein the polymer substance is a cationic substance. 6. The recording medium according to claim ² , wherein the total basis weight is 50 to 150 g / m ² . 7. A total component amount of the cationic substance and the polymeric substance, according to claim 2 which is 0.05~7g / m ²
The recording medium described. 8. The recording medium according to claim ² , wherein the total amount of components of the cationic substance and the polymer substance is 0.3 to 5 g / m ² . 9. The recording medium according to claim 2, wherein the weight ratio of the cationic substance and the polymer substance is 100: 1 to 1:20. 10. The recording medium according to claim 2, which is a recording paper obtained by impregnating the cationic substance and the polymer substance into a sheet material made of a fibrous substance and a filler. 11. The recording medium according to claim 2, which is a recording paper obtained by applying the cationic substance and the polymer substance on the surface of a sheet material made of a fibrous substance and a filler. 12. A recording medium comprising a sheet material composed of a fibrous substance and a filler as a main component, and further containing at least a pigment in addition to the cationic substance and the polymeric substance, the fibrous substance covering the pigment particles. A recording paper having a surface which is provided with a partially exposed fibrous material.
The recording medium described. 13. A sheet material comprising a fibrous substance and a filler as a main component, which is impregnated with the cationic substance, the polymeric substance and a pigment, or is applied on the surface of the sheet material, wherein the fibrous substance is a pigment. 3. A recording medium according to claim 2, which is a recording paper having a surface which is covered with the particles of the above and has a partially exposed fibrous substance. 14. The recording medium according to claim 10, wherein the polymer substance is a polymer substance having a molecular weight of 2000 or more and 10000 or less. 15. The recording medium according to claim 10, wherein the polymer substance is a cationic substance. 16. The recording medium according to claim 10, having a total basis weight of 50 to 150 g / m ² . 17. The recording medium according to claim 10, wherein the total amount of the components of the cationic substance and the polymer substance is 0.05 to 7 g / m ² . 18. The total amount of components of the cationic substance and the polymer substance is 0.3 to 5 g / m ^2.
The recording medium according to any one of 0 to 13. 19. The recording medium according to claim 10, wherein the weight ratio of the cationic substance and the polymer substance is 100: 1 to 1:20. 20. The recording medium according to claim 2, wherein the cationic substance and the polymer substance are applied to the surface of a plastic substrate to form an ink absorbing layer. 21. The recording medium according to claim 20, wherein the polymer substance is a polymer substance having a molecular weight of 2000 or more and 10000 or less. 22. The recording medium according to claim 20, wherein the polymer substance is a cationic substance. 23. The recording medium according to claim 20, wherein the total basis weight is 50 to 5000 g / m ² . 24. The basis weight of the ink absorbing layer is 0.2 to.
The recording medium according to claim 20, having a weight of 50 g / m ² . 25. The recording medium according to claim 20, wherein the total amount of the cationic substance and the polymer substance is 0.005 to 70% by weight of the ink absorbing layer. 26. The recording medium according to claim 20, wherein the weight ratio of the components of the cationic substance and the polymer substance is 20: 1 to 1:20. 27. An image forming method comprising forming a recorded image by applying an ink containing at least a water-soluble dye having an anionic group to the recording medium according to any one of claims 2 to 26. . 28. The image forming method according to claim 27, wherein the ink is applied by being ejected as droplets from the ejection orifice onto the recording medium in accordance with a recording signal. 29. The image forming method according to claim 27, wherein the ink is ejected by an inkjet method. 30. The image forming method according to claim 27, wherein the ink further contains an anionic compound. 31. The four colors of yellow, cyan, magenta, and black are used as the ink.
The image forming method described.