Recording material treatment liquid, recording material treated with same, and methods for producing same

Abstract

[Problem] To provide a recording material treatment liquid that can be discharged in an inkjet manner and does not affect the color tone of a medium even when the medium is coated with transparent fine particles, while forming a receiving layer which maintains the conventional ink bleed, feathering, print density, and bleeding. [Solution] The recording material treatment liquid contains at least (i) a water-soluble anionic polymer, (ii) a water-soluble cationic polymer, and (iii) a surfactant and is characterized in that the water-soluble anionic polymer (i) is one or more types from among styrene-acrylic acid copolymers, α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid copolymers.

Description

Treatment solution for recording material, recording material treated therewith, and method for manufacturing them.

[0001] The present invention relates to a processing liquid for a recordable material, a method for manufacturing a recordable material, and a recordable material, which can be ejected by inkjet printing, has high storage stability, and when coated onto a substrate to form an ink-receiving layer, improves the blurring, feathering, print density, and bleeding of printed material without changing the visible surface condition (e.g., transparency, opacity) of the substrate from before coating.

[0002] Generally, printer inks are broadly classified into organic solvent-based inks and water-based inks. Organic solvent-based inks have excellent water resistance, but they have problems with bleeding on plain paper, odor, and safety, so water-based inks have become the mainstream in recent years. Inkjet recording methods, in particular, can easily and inexpensively produce small quantities of a wide variety of images, and have been applied to various fields of printing on liquid-absorbing and non-liquid-absorbing substrates, such as printing text, documents, and photographs, printing labels, printing on fabrics, marking, color filters, and special printing such as circuit printing.

[0003] Inkjet inks are used on a variety of substrates for a variety of purposes, but when printing on substrates such as paper, film, and fabric for the purpose of visual recognition, high density of images and text and vivid colors are desired. Because images and text are composed of fine ink dots, the ink must be quickly absorbed into the substrate, and even if the ink dots overlap, the ink must not flow out and diffuse laterally from the ink dots, resulting in smooth and sharp edges around the image and printed text.

[0004] Therefore, inkjet printing uses a lot of solvent in the ink to control printing speed and dot formation, but this causes deterioration of image quality such as print density, bleeding and feathering (a phenomenon in which ink droplets embedded in the recording material penetrate the surrounding area of ​​the image through the mesh of the recording material's constituent fibers such as cellulose, causing the image to appear fuzzy), and bleeding (a phenomenon in which ink from the image area bleeds into the unprinted area like whiskers at the boundary between the image and the unprinted area) that occurs when the solvent cannot be fully absorbed. For this reason, various measures are taken not only in the ink but also in the recording material, which is the substrate, to improve print quality.

[0005] Specifically, this method improves print quality by providing an ink-receiving layer on the material to be recorded. In this case, (1) in addition to improving print quality, (2) it is required that there be no problems such as stickiness or blocking on the surface of the receiving layer before and after printing, and (3) that the receiving layer does not cause unintended changes in texture such as loss of transparency or mattification, if the original color of the substrate is to be preserved in the non-printed areas. Furthermore, since there are advantages to forming the receiving layer itself using an inkjet method, (4) it is desirable that the receiving layer forming material be inkjet ejectable, and (5) it is required that the receiving layer forming material has storage stability, and that the processing steps are not excessively complicated and are industrially feasible.

[0006] As attempts to achieve these requirements, for example, the following methods have been proposed: (i) a method to prevent bleeding by rapidly absorbing the solvent in the ink by coating the surface of the recording material with a water-absorbing polymer and an inorganic porous pigment; (ii) a method to improve image quality by incorporating a cationic substance into the surface of the recording material to increase ink bleeding, feathering, and print density; (iii) a method to improve water resistance and prevent bleeding and feathering by treating the surface of the recording material with a treatment solution containing water-insoluble organic composite particles formed from a cationic polymer and anionic polymer (Patent Document 1); (iv) a method to suppress the stickiness of the coating film and improve film strength by using a crosslinkable cationic polymer (Patent Document 2); (v) a method to impart functionality by curing a crosslinkable resin on the surface of the recording material to form a porous coating film and then impregnating it with a cationic composition, etc. (Patent Document 3); (vi) a method to apply a pretreatment agent consisting of insoluble resin particles made of polyolefin resin and polyurethane resin, a flocculant and water using an inkjet (Patent Document 4); and (vii) a method to apply a specific amount of coating to a specific paper by performing a specific treatment using a cationic polymer (Patent Document 6).

[0007] However, while method (i) suppresses bleeding, it fails to improve ink bleeding, feathering, and print density, and also results in unintended surface properties such as decreased transparency, increased opacity, and matte finish. Furthermore, the high viscosity of the liquid and the presence of particles make inkjet ejection difficult. Method (ii) fails to prevent stickiness and bleeding. Method (iii) is effective in preventing bleeding, feathering, and bleeding, and improving print density on liquid-absorbing substrates such as paper and canvas, but it results in unintended surface properties such as decreased transparency, increased opacity, and matte finish. Furthermore, the high viscosity of the liquid and the presence of particles make inkjet ejection difficult. Another drawback is its poor effectiveness on non-liquid-absorbing substrates. Method (iv) solves the problem of stickiness caused by the blocking phenomenon exhibited by cationic polymers through crosslinking, but it has high viscosity, problems with application, and problems with product storage stability due to its crosslinking properties. Furthermore, crosslinking causes ink bleeding, feathering, and a decrease in print density. Method (v) requires forming a porous film first and then impregnating it with a cationic composition, making the coating process complex and impractical. Also, the impregnated cationic composition migrates due to the ink liquid or moisture after printing, causing problems such as ring bleeding. Method (vi) improves ink bleeding, feathering, and print density, but it requires micronizing emulsion aggregates for inkjet application, and improving bleeding requires constructing the coating film using a complex coating method, which is impractical. The presence of particles also causes changes in texture such as decreased transparency, increased opacity, and matte finish, resulting in unintended surface properties. Method (vii) produces effects on paper such as ink bleeding, feathering, print density, and bleeding, but it has problems on film, particularly with bleeding and blocking effects.

[0008] Patent No. 3015739, Patent No. 6510862, Patent No. 5341514, Patent No. 6988915, Patent No. 6712669, Japanese Patent Publication No. 2003-320745, Japanese Patent Publication No. 2007-38625

[0009] Thus, there is a need for a material that can form a receptive layer on various substrates, such as paper, woven fabric, and wood, that (1) has improved print quality with suppressed degradation of image quality such as print density, bleeding, feathering, and bleeding, (2) does not have problems such as stickiness or blocking on the receptive layer surface before and after printing, and (3) does not cause unintended changes in texture such as loss of transparency or mattification due to the receptive layer. In particular, there is a need for a method and material that can provide such a method, in which the formation of the receptive layer itself can be performed by an inkjet method, and the processing steps are not excessively complicated and are industrially feasible. The present invention solves these problems.

[0010] The inventors of this invention have diligently studied the above-mentioned problems. As a result, they have discovered that by generating transparent particles using a specific combination of materials and applying a liquid containing these particles to form an inkjet-receiving layer, it is possible to improve the print quality of printed materials without impairing the appearance or texture of the substrate, and moreover, the receptive layer can be formed in a simple manner using an inkjet method, thus arriving at the present invention.

[0011] In other words, the present invention provides: (1) a processing solution for a material to be recorded containing at least (i) a water-soluble anionic polymer, (ii) a water-soluble cationic polymer, and (iii) a surfactant, characterized in that (i) the water-soluble anionic polymer contains one or more of the following: styrene-acrylic acid copolymer, α-methylstyrene-acrylic acid copolymer, and styrene-α-methylstyrene-acrylic acid copolymer; and (2) the processing solution for a material to be recorded according to (1) above, characterized in that (iii) the surfactant is a compound represented by the following chemical formula.

[0012] In the formula, R １ R is a linear or branched alkyl group having 1 to 3 carbon atoms, n is an integer from 1 to 50, R ２ The following chemical formulas are used, where m is an integer from 1 to 3, and X is SO3M, -COOM, -PO ３ M ２ One or more of the following, M is NH4, Na, or Ca

[0013] (3) (ii) The treatment liquid for the material to be recorded according to (1) above, characterized in that the water-soluble cationic polymer is a compound represented by the following chemical formula.

[0014]

[0015] n is an integer between 1 and 10000.

[0016] (4) A processing liquid for a material to be recorded according to (1) above, characterized in that the weight ratio of (i) a water-soluble anionic polymer to (ii) a water-soluble cationic polymer is 100 to 500 parts of (ii) a water-soluble cationic polymer per 100 parts of (i) a water-soluble anionic polymer; (5) A method for producing a material to be recorded, characterized in that the processing liquid for a material to be recorded according to (1) above is applied to a substrate; (6) A method for producing a material to be recorded, characterized in that the processing liquid for a material to be recorded according to (1) above is applied to a substrate, wherein the substrate is a liquid-absorbing substrate;

[0017] (7) A method of recording on a recordable material, characterized by coating a base material with the recording solution described in (1) above, and recording on the recordable material with an ink containing a coloring agent; (8) An inkjet recording method, characterized by performing inkjet printing on a recordable material formed by coating a base material with the recording solution described in (1) above; (9) A method for manufacturing a recordable material, characterized in that, when performing inkjet printing on a recordable material formed by coating a base material with the recording solution described in (1) above, the coating by an inkjet method is performed in a continuous manner.

[0018] The recording material treatment liquid of the present invention can be applied to any substrate, and the recording material of the present invention can be obtained by applying it. That is, the recording material treatment liquid of the present invention can be used as a treatment liquid for impregnation and coating (the coating method is not limited) of various substrates (the substrate is not limited), i.e., a recording material treatment liquid, and a coated layer can be formed on the substrate in this way.

[0019] The formed layer functions as a so-called receptive layer, receiving ink when colored ink or other inks are printed on it (whether text, graphics, or solid colors). A typical example is the inkjet ink receptive layer formed on the surface of inkjet printing paper, but it is not limited to this; any layer formed on the substrate to be printed on for purposes such as facilitating ink fixation and color development is acceptable. A material on which such a receptive layer is formed is called a recording material.

[0020] The receiving layer formed by the present invention improves inkjet printing performance, including ink bleeding, feathering, print density, and ink bleeding. Furthermore, it can be an ink receiving layer that does not block the coating even when applied to substrates such as resin films or glass. The present invention provides a processing liquid for recording materials that can form a recording material having such an excellent receiving layer. In addition, the processing liquid itself has excellent storage stability. Moreover, since the processing liquid is transparent and the coated layer formed by applying the processing liquid is also transparent, the original color of the substrate can be preserved.

[0021] Figure 1 illustrates the representation of each component in Figures 2 and 3. Figure 2 is a conceptual diagram showing the state of the anionic polymer, cationic polymer, and surfactant in the receiving layer of the present invention. Figure 3 is a conceptual diagram showing the state when ink is dropped into the receiving layer of the present invention.

[0022] The recording medium processing solution of the present invention contains at least (i) a water-soluble anionic polymer, (ii) a water-soluble cationic polymer, and (iii) a surfactant. Of these, (i) the water-soluble anionic polymer has an anionic functional group and is characterized in that the polymer is one or more of the following: styrene-acrylic acid copolymer, α-methylstyrene-acrylic acid copolymer, or styrene-α-methylstyrene-acrylic acid copolymer. These components may interact with each other in the processing solution to undergo chemical reactions or form complexes. In addition to the components (i) to (iii) above, the recording medium processing solution of the present invention may also contain components such as binders. The following describes each component.

[0023] 1. Description of Materials [Water-soluble anionic polymer] (i) A water-soluble anionic polymer is an anionic polymer that is water-soluble. An anionic polymer is a polymer having an anionic functional group, and generally refers to what is called an anionic polymer. Here, an anionic functional group does not matter whether it is ionized or can be ionized. For example, a carboxyl group ionizes upon alkali addition and exhibits anionic properties, so regardless of whether it is ionized or not, it falls under the category of an anionic functional group in this invention, and therefore materials having such a functional group are considered anionic polymers.

[0024] The water-soluble anionic polymer may be one that is water-soluble from the start, or an anionic polymer that is not water-soluble may be made water-soluble. Generally, as the anionic polymer, a polymer having anionic functional groups such as a carboxyl group, a sulfonic acid group (SO3H), a sulfuric acid ester group, or a phosphate ester group can be used, and water solubility can be imparted to it by adding an alkaline substance such as ammonia, an organic amine, or an alkali metal to anionize it. In the present invention, the water-soluble anionic polymer is characterized by containing one or more of the following: styrene-acrylic acid copolymer, α-methylstyrene-acrylic acid copolymer, or styrene-α-methylstyrene-acrylic acid copolymer. These styrene-acrylic acid copolymers, α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid copolymers are generally collectively referred to as "styrene-acrylic copolymer" or "styrene-acrylic acid resin." These anionic polymers can be used individually or in mixtures of two or more.

[0025] Examples of alkaline substances used to impart water solubility include those generally known as neutralizing agents, such as organic amines like trimethylamine, triethylamine, tri-n-propylamine, tributylamine, triethanolamine, aminomethylpropanol, aminomethylpropanediol, aminoethylpropanediol, trihydroxymethylaminomethane, monoethanolamine, and triisopropanolamine, as well as inorganic alkali salts such as aqueous ammonia, potassium hydroxide, and sodium hydroxide. These are suitable because they provide stable water solubility. Aqueous ammonia is particularly suitable because it is easily volatile and removed.

[0026] By selecting anionic polymers, particularly those with high glass transition temperatures, the blocking of coating films can be further improved. Furthermore, selecting polymers with high softening points also contributes to improved blocking. The glass transition temperature is the temperature at which a resin, when heated above a certain temperature, becomes more pliable and enters a soft, rubbery state; it is the temperature at which the properties of the resin change rapidly. The glass transition temperature is 50°C or higher, preferably 50°C to 140°C. The glass transition temperature is higher in styrene-acrylic acid copolymers, α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid copolymers as the monomer content ratio of styrene and α-methylstyrene increases. The composition ratio of styrene and α-methylstyrene in the polymer is 20% to 80%, preferably 50% to 80%, and more preferably 60% to 75%. Furthermore, the higher the proportion of α-methylstyrene in the composition ratio of styrene to α-methylstyrene, the higher the glass transition temperature. A low glass transition temperature can lead to blocking problems, as well as the fusion of generated particles, resulting in larger particle sizes. If the concentration is too high, the composition ratio with carboxylate-containing acrylic acid, etc., may be disrupted, making it impossible to achieve water solubility. The higher the proportion of styrene and α-methylstyrene, the more hydrophobic the resin becomes, resulting in a rigid, less flexible polymer, which leads to improved blocking properties. Furthermore, the higher the proportion of α-methylstyrene, the higher the hydrophobicity becomes, resulting in a rigid, less flexible polymer, which further improves blocking properties.

[0027] The softening point indicates the temperature at which the resin begins to soften and deform when heated. The softening point is 100°C or higher, preferably 140°C or higher, and more preferably 150°C or higher. Below 100°C, blocking problems occur. In applications where printed materials are transferred by heat, a low softening point can lead to the problem of transfer occurring in areas other than the printed surface.

[0028] The weight-average molecular weight (Mw) of the polymer is preferably 20,000 to 5,000. More preferably, 10,000 to 18,000, and even more preferably, 10,000 to 17,000 can be suitably used. If the molecular weight is too low, the glass transition temperature will be lowered, which will not lead to improved blocking, and if the molecular weight is too high, the composition ratio with carboxylic acid-containing acrylic acid, etc., will be disrupted, and water solubility will not be achieved. The amount of carboxylic acid functional groups is determined by the acid value.

[0029] Among the aforementioned anionic polymers, α-methylstyrene-acrylic acid copolymers and styrene-α-methylstyrene-acrylic acid copolymers can be suitably used in terms of the applicability of the processing solution to the recording material, printing characteristics during recording, and blocking improvement. Specifically, commercially available products such as Joncryl 678, 690, and JDX-C3080 (all manufactured by BASF Japan Ltd.) can be used, and these can be solubilized with any alkaline agent as described above. In addition, Joncryl 60J, 70J, and JDX-6180 (all manufactured by BASF Japan Ltd.), which are products in which polymers having these anionic functional groups have been solubilized, can also be used.

[0030] The pH of water-soluble anionic polymers is usually set to 8 or higher to achieve stable water solubility. The acid value of water-soluble anionic polymers is preferably 50 to 300 mgKOH / g, more preferably 60 to 250 mgKOH / g, and more preferably 70 to 250 mgKOH / g, from the viewpoint of inkjet printing performance, such as ink bleeding, feathering, and print density. In particular, water-soluble anionic polymers exhibit extremely excellent performance when the acid value is in the range of 235 mgKOH / g to 260 mgKOH / g, and even more preferably 235 mgKOH / g to 250 mgKOH / g, and especially 235 mgKOH / g to 245 mgKOH / g. If the acid value is below 50 mgKOH / g, stable water solubility cannot be obtained, and if it is above 300 mgKOH / g, ink bleeding, feathering, and print density may decrease.

[0031] [Water-soluble cationic polymers] (ii) Water-soluble cationic polymers refer to cationic polymers, that is, polymers having cationic functional groups that are water-soluble. Examples of cationic polymers include polyamines, polyamine sulfones, polyvinylamines, polyvinylpyridines, polyethyleneimines, polyethyleneimines-epichlorohydrin reaction products, polyamidoamines, polyacrylamides, polydiallyldimethylammonium chlorides, polyamidoamine-epichlorohydrin resins, dicyanamide-formaldehyde resins, urea-formaldehyde resins, etc., which can be used individually or in combination of two or more. Particularly preferably, water-soluble cationic polymers are selected from one or more compounds represented by the following chemical formulas.

[0032]

[0033] n is an integer between 1 and 10000.

[0034] Examples of commercially available products of this type include Unisense FPA102L (diallyldimethylammonium chloride), Unisense FCA1000L (poly(acrylamide-co-diallyldimethylammonium chloride)), Unisense ZCA1000L (diallyldimethylammonium acrylate chloride), Unisense KHE100L (dimethylamine-epichlorohydrin-ammonia condensate), Unisense KHL10L (dicyandiamide formalin condensate), and Unisense KHP11L (dicyandiamide diethylenetriamine condensate), all manufactured by Senka.

[0035] [Surfactants] (iii) The type of surfactant is not limited, but ionic surfactants are particularly preferred, and anionic surfactants are even more preferred. Typical examples include so-called polymer dispersants, such as styrene-ethylene oxide anhydride adducts. Most preferably, the compound is represented by the following chemical formula. In the formula, R １ R is a linear or branched alkyl group having 1 to 3 carbon atoms, n is an integer from 1 to 50, R ２ The following chemical formulas are used, where m is an integer from 1 to 3, and X is SO3M, -COOM, -PO ３ M ２ One or more of the following, M is NH4, Na, or Ca n is preferably 5 to 50. X is preferably SO3M. M is preferably NH4 or Na. Preferred compounds include, for example, polyoxyethylene styrene-phenyl ether sulfate ammonium, polyoxyethylene lauryl ether sulfate ammonium, polyoxyethylene styrene-phenyl ether, polyoxyethylene styrene-phenyl ether sulfate ammonium, polyoxyethylene polyoxypropylene polycyclic phenyl ether, and polyoxyethylene polyoxypropylene polycyclic phenyl ether sulfate salt. Among these, polyoxyethylene styrene-phenyl ether sulfate ammonium and polyoxyethylene polyoxypropylene polycyclic phenyl ether sulfate salt are particularly preferred. Compounds having the following structure are also particularly preferred. Preferable commercially available products include, for example, "Hitenol NF-08", "Hitenol NF-17", "Noigen EA-207D", "Noigen EA-157", "Newcol 710-F", "Newcol 714-F", "Newcol 2600-FB", "Newcol 2616-F", "Newcol CMP-60-SF", and "Newcol 707-SF". Among these, "Hitenol NF-08", "Hitenol NF-17" and "Newcol 707-SF" are particularly preferable.

[0036] [Dispersion Medium] There is no particular limitation as long as it is a liquid medium in which the aforementioned components (i) to (iii) can exist uniformly, but water or an aqueous medium is usually preferable. Regarding the blending amount, the concentration of (i) the water-soluble anionic polymer may be 0.1 to 15.0 wt%, particularly preferably 1.0 to 10.0 wt%, and more preferably 2.0 to 6.0 wt%.

[0037] [Blending Ratio] Regarding the blending ratio of the aforementioned components (i) to (iii), the weight ratio of (i) the water-soluble anionic polymer to (ii) the water-soluble cationic polymer is preferably 100 to 500 parts by weight of (ii) the water-soluble cationic polymer relative to 100 parts by weight of (i) the water-soluble anionic polymer. It is particularly preferably 140 to 400 parts by weight, and more preferably 150 to 370 parts by weight. When the blending amount of (ii) the water-soluble cationic polymer exceeds 500 parts by weight relative to 100 parts by weight of (i) the water-soluble anionic polymer, the stability, particularly the viscosity at a high temperature of 50°C, tends to increase. When it is less than 100 parts by weight, separation and white precipitation may occur. The blending amount of (iii) the surfactant is 10 to 100 parts by weight of the surfactant relative to 100 parts by weight of the total of (i) the water-soluble anionic polymer and (ii) the water-soluble cationic polymer, preferably 15 to 50 parts by weight, more preferably 20 to 40 parts by weight. The most excellent performance can be obtained within this range. When added in an amount exceeding 100 parts by weight, stickiness after drying becomes strong, and when added in an amount less than 10 parts by weight, solubilization is insufficient, which may lead to white turbidity and precipitation.

[0038] 2. Preparation of the Treatment Solution The treatment solution of the present invention can be prepared by mixing the water-soluble anionic polymer, the water-soluble cationic polymer, and a surfactant. Alternatively, the mixing order can be as follows: first, the water-soluble anionic polymer and stabilizer are homogenized in water, then the water-soluble cationic polymer is added, and precipitation occurs while stirring, followed by the addition of the surfactant. When the water-soluble anionic polymer and the water-soluble cationic polymer are mixed, particles are generated and precipitate (for example, Patent Document 1). This can be easily identified by the fact that the mixture becomes cloudy and loses its fluidity. It is presumed that the anions of the water-soluble anionic polymer are attracted to and approach the water-soluble cationic polymer, generating particles. Adding a surfactant to this solution causes it to become transparent. This is thought to be because micelles are formed by the surfactant, and the particles are solubilized. While this method can be used in the present invention, it is complicated and can cause problems because it involves agglomeration followed by solubilization. Therefore, a method can be proposed in which the water-soluble anionic polymer and surfactant are mixed first, and then the water-soluble cationic polymer is added. In this case, the addition of the water-soluble cationic polymer initially causes loose white aggregation, but continued stirring can generate a transparent anion-cationic complex. This is thought to be because, when a cationic polymer is added to a system containing an anionic polymer and a surfactant, the anionic polymer and the cationic polymer interact to form an anionic-cationic complex, while the surfactant contributes to its solubilization. In other words, it is thought that the hydrophobic portions of the anionic polymer and the surfactant interact (π-π bond) to stabilize and maintain stability. For this reason, particularly excellent effects are observed when an anionic polymer having aromatic rings such as benzene rings, for example, styrene-acrylic polymers, is used, and a surfactant also having aromatic rings such as benzene rings, for example, the compound shown in the chemical formula above, is used. Therefore, with the method of mixing the above three components, it is possible to precipitate the on-cationic complex beforehand and then make it transparent, or to add the cationic polymer to the mixture of anionic polymer and surfactant, or to mix all of them simultaneously.However, as explained above, the most efficient and preferable method is to pre-mix the anionic polymer and surfactant and then add the cationic polymer to it.

[0039] Since water-soluble anionic polymers and water-soluble cationic polymers are usually in the form of 15 wt% to 70 wt% aqueous solutions, it is often unnecessary to add additional dispersion media such as water. The water-soluble cationic polymer can also be dissolved in an aqueous solution before mixing. While the concentrations of these components during the reaction are not limited, an optimal concentration exists based on viscosity stability and the state after water dilution. The optimal concentration should be selected according to the application and the solvent composition of the inkjet ink used for printing.

[0040] Various types of agitators can be used for stirring. Specifically, dissolver mixers, homogenizers, shear mixers (homomickers, ultramixers), and disperser mixers suitable for high viscosity materials can be used.

[0041] The coating solution obtained in this way is a transparent liquid and maintains its transparency even after being applied to a substrate, without impairing the visual texture of the substrate. It is presumed that when the micelles come into contact with the liquid components in the ink (especially solvent components other than water, such as alcohol, diol, glycol, etc.), the particles become insoluble in water, aggregate and precipitate, and absorb the liquid components and expand, thereby preventing bleeding. Furthermore, it is presumed that the anionic functional groups such as carboxyl groups of the water-soluble polymer immobilize the cationic functional groups, and through the action of these cationic functional groups, the anionic pigments and dyes are immobilized on the water-soluble polymer via the cationic polymer, thereby improving water resistance defects such as ring bleeding, and improving ink bleeding, feathering, and print density. More specifically, as shown in Figures 1, 2, and 3, the anionic polymer and the cationic polymer form a complex based on electrostatic interaction, and the benzene ring of the anionic polymer and the benzene ring of the surfactant interact to solubilize, forming a transparent coating solution and a receiving layer. Here, when ink is ejected, the hydrophilic-hydrophobic balance of the surfactant is disrupted by the solvent in the ink droplet, preventing it from contributing to the solubilization of the complex. As a result, the complex aggregates and becomes denser, which is presumed to strongly hold the colorants in the ink at high density, improving printing performance.

[0042] [Processing Solution for Recording Material] In the present invention, the processing solution obtained by mixing the aforementioned water-soluble anionic polymer, water-soluble cationic polymer, and surfactant can be used as is, or a binder such as PVP (polyvinylpyrrolidone) can be added. By adding a binder, it can be uniformly applied to the substrate and has an excellent effect of forming a coating film as a film-forming component to hold the polymer metal composite particles of the present invention to the substrate. The binder is not particularly limited as long as it can form a film and is compatible with other components in the processing solution, and in addition to PVP, various anionic and nonionic binders can be selected. The amount of binder to be added is not particularly limited, and is 1 to 20% by weight, more preferably 1 to 10% by weight, and even more preferably 2 to 5% by weight of the total processing solution. The content in the processing solution is 10 to 300 parts by weight, more preferably 20 to 200 parts by weight, and even more preferably 30 to 100 parts by weight, per 100 parts by weight of solids in the processing solution.

[0043] [Other Materials] The recording material processing liquid of the present invention may contain additives as needed, to the extent that the objectives of the present invention are not hindered, such as viscosity modifiers such as polyvinylpyrrolidone and polyvinyl alcohol, and stabilizers such as styrene-ethylene oxide adducts, in order to improve fluidity. As viscosity modifiers (thickeners), thickening polysaccharides such as salt-tolerant xanthan gum and matarind seed gum, cellulosic thickeners such as hydroxyethylcellulose, hydroxymethylcellulose, and hydrophobized hydroxypropylmethylcellulose, and thickening components such as PVP (polyvinylpyrrolidone) may also be added. In addition to these, other additives such as surface sizing agents, gelatin, casein, starch, modified starch, starch derivatives, glue, carboxymethylcellulose and other cellulose derivatives, algin and other surface sizing agents, synthetic rubber emulsions such as styrene-butadiene rubber and acrylonitrile-butadiene rubber, styrene-maleic acid copolymer, polyvinyl acetate, ethylene vinyl acetate copolymer, ketene dimer, colloidal silicate unsaturated polyester resin, polyvinyl butyrate, alkyd resin, epoxy resin, pigment dispersants, thickeners, fluidity modifiers, defoaming agents, foam inhibitors, mold release agents, foaming agents, penetrating agents, water-resistant agents, humectants, preservatives, antioxidants, fluorescent whitening agents, UV absorbers, coloring dyes, titanium dioxide, calcium carbonate, satin white, barium sulfate, talc, silica, clay zinc oxide, aluminum hydroxide and other coloring pigments can also be incorporated. For applications requiring film toughness, such as film manufacturing, it is advisable to include crosslinking components. For applications requiring higher blocking resistance, it is recommended to include wax particles or silicone.

[0044] These materials are preferable because, after mixing the aforementioned anionic polymer, water-soluble cationic polymer, and surfactant to produce transparent particles and preparing the treatment solution of the present invention, adding them to the solution leads to an improvement in the quality of the treatment solution and the receiving layer.

[0045] The processing solution for recording materials obtained as described above provides improved bleeding and feathering, increased print density, and enhanced water resistance when printed with an inkjet printer.

[0046] [Preparation of the recording material] The recording material of the present invention is obtained by treating a coating film (substrate) with the above-mentioned recording material treatment liquid.

[0047] The aforementioned coated material is intended to have an effect on absorbent materials. For example, paper made primarily from non-wood fibers or plant fibers that are wood fibers, paper made from kenaf, a pulp raw material plant that is not wood, and synthetic paper. Absorbent materials such as woven fabrics made from materials such as cotton, hemp, and polyester fibers, wooden boards, wooden planks, and nonwoven fabrics such as PP and PET, as well as transparent or opaque resin sheets or films such as polyester, polystyrene, polyvinyl chloride, polyethylene, polycarbonate, polypropylene, polyolefin, polyethylene terephthalate, polycarbonate, polymethyl methacrylate, and cellulose acetate are examples, but the present invention is not limited to these examples. In the present invention, among these absorbent materials, paper made primarily from non-wood fibers or plant fibers that are wood fibers, paper made from kenaf, a pulp raw material plant that is not wood, and synthetic paper, woven fabrics made from materials such as cotton, hemp, and polyester fibers, wooden boards, wooden planks, and nonwoven fabrics such as PP and PET have an excellent effect on ink bleeding, feathering, print density, and bleeding performance.

[0048] Methods for treating the substrate with the aforementioned recording material treatment liquid include, for example, applying the recording material treatment liquid to the substrate by coating methods such as coating, impregnation, or inkjet printing, and can be selected according to the type and material of the substrate used.

[0049] Examples of coating methods include size press methods such as the horizontal size press method, roll bead coater method, and calender size press method; knife coater methods such as the air knife coater method; transfer roll coater methods such as the gate roll coater method; roll coater methods such as the direct roll coater method, reverse roll coater method, and squeeze roll coater method; blade coater methods such as the bill blade coater method, short duel coater method, and two-stream coater method; bar coater methods such as the rod bar coater method; cast coater method, gravure coater method, curtain coater method, die coater method, spray coater method, and brush coater method. Examples of impregnation methods include the pre-wetting method, float method, and doctor bar method.

[0050] In the aforementioned inkjet printing method, the processing liquid for the recording material is used as ink, and the necessary parts are coated with it before printing with color ink. Since the processing liquid for the recording material does not contain inorganic pigment particles, it is less likely to cause nozzle clogging. This inkjet coating method can also be performed in a continuous manner.

[0051] The amount of the processing liquid for the recording material applied varies depending on the type of substrate and cannot be determined in general terms. However, in the case of a non-absorbent liquid substrate, in order to obtain inkjet printing performance such as ink bleeding, feathering, print density, and bleeding performance, the dry film thickness is preferably 0.7 to 5 μm, and more preferably 0.7 to 5 μm. If the dry film thickness is too thin, bleeding occurs because the retention capacity of the liquid portion of the ink is low. If it is too thick, the uniformity and smoothness of the coating film tend to be impaired. After processing the substrate with the processing liquid for the recording material, the substrate should be dried. The drying method is not particularly limited, but examples include hot air drying, infrared drying, and drum drying. The recording material thus obtained has been treated with the processing liquid for the recording material and therefore has the excellent property of improving the clarity and density of the recorded image. Furthermore, when the substrate is a transparent resin film, the recording material has excellent transparency of the ink receiving layer and is therefore suitably used for printing on canvas, paper, and wood with high design appeal. The recording material having the processing solution and receiving layer of the present invention exhibits particularly excellent performance in IJ printers equipped with pigment inks, and is also suitably used with laser printer inks and gravure inks as printing inks. These printing processes can also be carried out continuously.

[0052] [Examples and Comparative Examples] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. Parts and % refer to parts by weight and weight percent, respectively.

[0053] (Example 1) [Preparation of liquid mixture] 50.0 g of deionized water and 19.0 g of water-soluble anionic polymer (product name "JONCRYL 70J", ammonium neutralized salt of styrene acrylic polymer manufactured by BASF (solids content 30 wt%)) as the active ingredient were mixed, and 4.00 g of compound 1 ("Hythenol NF-17" (polyoxyethylene styrene-phenyl ether sulfate ammonium, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)) was added as a surfactant, and the mixture was mixed for 10 minutes or more until it was uniform in appearance. Furthermore, 27.0 g of a water-soluble cationic polymer (product name "Papiogen P-105", manufactured by Senka Co., Ltd., a dimethylamine-epichlorohydrin-ammonia condensate) was added all at once, and the mixture was stirred for more than 1 hour to obtain a transparent liquid mixture. (Comparative Example 1) A liquid mixture was obtained in the same manner as in Example 1, except that the materials and mixing ratios were changed as shown in the Comparative Example 1 column of Table 1. The mixing ratio values ​​in Table 1 are listed as weight percent on a solid content basis for each material. Except for the components listed in the table, ion-exchanged water was added to make a total of 100%. The liquid mixture obtained in Comparative Example 1 was cloudy and did not become transparent even with continued stirring.

[0054] [Evaluation of Liquid Mixtures] <Method for Measuring Viscosity> The viscosity of the liquid mixture was measured using the following method. An E-type viscometer was used to measure viscosity at a liquid temperature of 25°C and 50 revolutions per minute. However, the number of revolutions per minute was adjusted as appropriate according to the viscosity of the substance being measured. The viscosity on the day the liquid mixture was prepared is listed as "Initial Viscosity" in Table 1.

[0055] (Visual Stability Assessment) 50g portions of the liquid mixture were placed in plastic containers (50cc iBoy, manufactured by AS ONE Corporation) and stored at room temperature and 50°C for one month, respectively. The condition after one month was visually inspected. Visual observation revealed that some maintained transparency (○), some showed slight turbidity (△), some were completely cloudy, some showed a cloudy sedimentary layer and separated into two layers, and some were transparent but separated into two layers: an aqueous phase and an oil phase (×). The results are shown in Table 1.

[0056] (Viscosity change over time) The liquid mixture was placed in a sealed container and stored at room temperature and 50°C for one month each. The viscosity was measured initially (on the day the liquid mixture was prepared) and after one month. The results of the evaluation, based on the percentage change in viscosity after one month relative to the initial viscosity, are shown in Tables 1 to 3. The viscosity measurement method is the same as for the initial viscosity. ◎ ±2 of initial viscosity 〇 ±5 of initial viscosity △ ±15 of initial viscosity × ±15 or more of the initial value

[0057] <Checking for Stickiness> A single drop of the liquid mixture was dropped onto a PET film using a void, and after drying at room temperature (12 hours), the presence or absence of stickiness was checked by touch. The results of the evaluation according to the following criteria are shown in the table. ○ Not sticky △ Slightly sticky × Sticky

[0058] <Evaluation of application to textile products> (Test specimen preparation) A 5cm x 5cm pongee fabric was impregnated with the liquid mixture at a pick-up rate of 100% and dried at 110°C for 5 minutes to create a printed test specimen. (Confirmation of stickiness) Immediately after drying, the surface of the printed test specimen was touched to check for stickiness. The results were evaluated according to the above criteria and are shown in the table. ◎: No stickiness 〇: Slightly sticky ×: Sticky, substances (dust in the air, etc.) adhere to the surface

[0059] <Applicability to copy paper> A 10 wt% diluted solution was prepared by diluting 10 parts by weight of the liquid mixture with 90 parts by weight of deionized water and mixing. Upon mixing, some solutions became uniform, some produced coarse aggregates, and some separated into two layers. Table 1 shows uniform solutions with ○ and non-uniform solutions such as those with coarse aggregates with ×. This 10 wt% diluted solution was then attempted to be applied to copy paper using a bar coater #6. Of these, the non-uniform solutions, such as those that separated into two layers, adhered to the coater and could not be spread in a film-like manner on the copy paper. The solutions that were able to be made uniform could be applied to copy paper using a bar coater #6. After application, the solution was dried at 125°C for 1 minute, and the following print evaluation was performed.

[0060] <Printing Evaluation> The diluted solution was applied by the method described above, and a printing test pattern was printed on dried copy paper using an IJ printer "PX105" manufactured by Seiko Epson Corporation under the conditions of "Super Fine Paper" and "High Quality Mode", and the following evaluations were performed.

[0061] (Visual Observation) After printing, drying at 80°C for 3 minutes and standing overnight at room temperature, the state was visually checked from the aspects of bleeding and feathering. The evaluation results of bleeding from the following aspects are shown in the table. ○: Printing is clear ×: Printing is unclear due to bleeding The evaluation results of feathering from the following aspects are shown in the table. ○: Ink does not spread along fibers ×: Ink spreads along fibers

[0062] (Check for Stickiness) The sticky state of the printed surface was checked by touching. ○: No stickiness △: Slight stickiness ×: Sticky

[0063] <Water Reactivity Evaluation> The liquid mixture was mixed in the ratios of liquid mixture (parts by weight) / ion-exchanged water (parts by weight) = 75 / 25, 50 / 50 and 25 / 75 respectively to prepare 75wt%, 50wt% and 25wt% diluted solutions. Immediately after these diluted solutions were prepared, they were visually observed to check whether turbidity occurred. The case with no turbidity is evaluated as ○, and the case with any turbidity is evaluated as ×, and the results are shown in the table. Items that have not been evaluated are marked with "-" in the table.

[0064] <IJ Ejection Performance Evaluation> (Check of Physical Property Values for IJ Ejection with Liquid Mixture) For the liquid mixture of Example 17, the particle diameter (D50) and surface tension were measured. D50 was measured using "Nanotrac Wave II" manufactured by Microtrac Corporation (particle refractive index: 1.51, shape: non-spherical, density: 1.00g / cm 3The measurements were performed under solvent conditions (water). Surface tension was measured using the Wilhelmy method with a Kyowa Interface Science Co., Ltd. automatic surface tension meter "DY-300". D50 was 9 nm and surface tension was 43.3 mN / m. Similarly, D50 was measured for the liquid mixture of Comparative Example 1, and viscosity was also measured (B-type viscometer, liquid temperature 25°C, measured at 60 rpm). D50 was 1380 nm and viscosity was 102 mPa·s. The recommended viscosity for the head used for IJ dispensing below is 3.2 to 4.4 mPa·s, and the measured value for Comparative Example 1 is far outside this range. Also, a D50 of 1380 nm was judged to be too large for IJ dispensing, so surface tension measurement and IJ dispensing tests were not performed for the liquid mixture of Comparative Example 1.

[0065] (Confirmation of physical properties of ink for IJ ejection) Using the liquid mixture of Example 25, an ink for IJ ejection was prepared with the formulation shown in Table 7, and the following evaluations were performed, yielding the following results. Note that the formulation ratios in Table 7 are weight ratios. ・Filterability of 3μm cellulose membrane filter: 100g could be filtered completely. ・Evaluation of water reactivity (a 25wt% diluted solution was prepared and the presence or absence of turbidity was checked): There was no turbidity.

[0066] (IJ ejection test) Using the above IJ ejection ink and a Seiko Epson S800-A1 print head, the ejection status was checked. - Ejection was good, and there were no print heads that failed to eject. - There was no flight curvature (curvature of droplet flight as measured by a drop watcher). - Intermittent ejection (re-ejection after an intermittent period of about 10 seconds) was possible, and there was no delay in re-ejection. - When drawing (ejection at 300 dpi onto PET film) and observing the dots under a microscope, the dots were of good precision, and no dot irregularities were observed.

[0067] (Examples 2-26, Comparative Examples 2-16) Liquid mixtures were prepared and evaluated in the same manner as in Example 1, except that the materials and mixing ratios were changed as shown in Tables 1-3. The component values ​​in Tables 1-3 are listed as weight percent of the solid content of each material. In addition to the components listed in the table, ion-exchanged water was used. Some of the obtained liquid mixtures were not transparent. The transparency of the liquid is indicated in the "Transparency" column in the table. Transparent is marked with ○, and non-transparent is marked with ×.

[0068] Table 1. Formulation and Evaluation (Examples 2-7, Comparative Examples 2-8)

[0069]

[0070] (Examples 8-17, Comparative Examples 9-11) Table 2 Formulation and Evaluation

[0071]

[0072] (Examples 18-26, Comparative Examples 12-16) Table 3 Formulation and Evaluation

[0073]

[0074] Table 4 Materials ((i) Water-soluble anionic polymers)

[0075] Table 5 Materials ((ii) Water-soluble cationic polymers)

[0076]

[0077] Table 6 Materials ((iii) Surfactants)

[0078]

[0079]

[0080] From the results of Examples 1 to 7, it can be seen that anionic polymers with a styrene ratio of 50% to 80%, particularly 60% to 75%, and among these, anionic polymers 1 and 6, which have an acid value of 235 mg KOH / g to 260 mg KOH / g, and moreover 235 mg KOH / g to 250 mg KOH / g, and especially 235 mg KOH / g to 245 mg KOH / g, are excellent. In particular, combinations of these anionic polymers with a compound that is polyoxyethylene styrene-phenyl ether ester as a surfactant, particularly surfactant 1 or surfactant 2 which is polyoxyethylene styrene-phenyl ether sulfate ammonium, and especially combinations of these with a condensate of dialkylamine and ammonia as a cationic polymer, show particularly excellent performance in various aspects. Furthermore, the results from other examples and comparative examples show that the combination of the above-mentioned anionic polymers, particularly those with a molecular weight (Mw) of 10,000 to 18,000, especially 10,000 to 17,000, with a surfactant and a cationic polymer such as a condensate of dialkylamine and ammonia or diallyldimethylammonium chloride, which has acrylamide or acrylic acid in its structure, exhibits extremely excellent effects. In addition, as can be seen from the <Applicability to copy paper>, the liquid mixture itself has the ability to form a coating film and can be used as a coating solution without adding further polymer components. Furthermore, as can be seen from the <Evaluation of application to textile products>, it was confirmed that it also contributes to improving printability on textiles. In addition, in the (visual stability evaluation) of the liquid mixture, even if it is transparent at the time of preparation, turbidity, sedimentation, and two-phase separation may occur over time. It is presumed that this is because the particles generated by the reaction of each component swell and become larger, or the particles aggregate with each other, resulting in a state that is visible as turbidity due to light scattering, or further, a state where it becomes turbid and a white precipitate is formed. Furthermore, it is presumed that in the case of the two-phase separation, the affinity between the components was low, causing the micelles to become unstable and unable to maintain an emulsified state.In contrast, the liquid mixture obtained from the combination of components of the present invention, particularly the combination of the above-mentioned particularly preferred components, and the coating solution obtained by diluting or inking it, maintain transparency without such time-related problems, exhibit high stability, and have excellent inkjet ejection properties.

[0081] The present invention provides a processing liquid for a recordable material that is transparent, does not affect the color tone of the media, and is inkjet ejectable, while maintaining inkjet printing performance such as ink bleeding, feathering, print density, and bleeding.

Claims

1. A processing solution for a material to be recorded, comprising at least (i) a water-soluble anionic polymer, (ii) a water-soluble cationic polymer, and (iii) a surfactant, wherein (i) the water-soluble anionic polymer is one or more of the following: styrene-acrylic acid copolymer, α-methylstyrene-acrylic acid copolymer, and styrene-α-methylstyrene-acrylic acid copolymer.

2. (iii) The treatment solution for the material to be recorded according to claim 1, characterized in that the surfactant is a compound represented by the following chemical formula. In the formula, R １ R is a linear or branched alkyl group having 1 to 3 carbon atoms, n is an integer from 1 to 50, R ２ The following chemical formulas are used, where m is an integer from 1 to 3, and X is SO3M, -COOM, -PO ３ M ２ One or more of the following, M is NH4, Na, or Ca 3. The treatment liquid for recording material according to claim 1, characterized in that the water-soluble cationic polymer is one or more compounds represented by the following chemical formulas. n is an integer between 1 and 10000.

4. The processing liquid for recording material according to claim 1, characterized in that the weight ratio of (i) a water-soluble anionic polymer to (ii) a water-soluble cationic polymer is 100 to 500 parts of (ii) a water-soluble cationic polymer per 100 parts of (i) a water-soluble anionic polymer.

5. A method for manufacturing a material to be recorded, characterized by applying the treatment liquid for the material to be recorded described in claim 1 to a substrate.

6. A method for manufacturing a material to be recorded, characterized by coating a substrate with the processing liquid for the material to be recorded according to claim 1, wherein the substrate is a liquid-non-absorbent substrate.

7. A method for recording on a recording material, characterized by recording on the recording material, which is obtained by coating a base material with the processing liquid for recording material described in claim 1, using an ink containing a coloring agent.

8. An inkjet recording method characterized by performing inkjet printing on a recording material formed by coating a substrate with the processing liquid for recording material described in claim 1.

9. A method for manufacturing a recordable material, characterized in that, when performing inkjet printing on a recordable material formed by coating a substrate with the processing liquid for recordable material described in claim 1, the coating is performed continuously using an inkjet method.

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