JP2005169796A - Recording medium, its manufacturing method and image forming method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording medium which can form a recording image with a silver salt photograph-level texture and quality, has an excellent fastness of a recording image and is free from a deterioration in picture quality, and its manufacturing method and an image forming method. <P>SOLUTION: In the recording medium comprising a substrate and an ink receiving layer provided on the substrate, wherein the ink receiving layer is constituted of at least two layers and the outermost surface layer contains aluminum oxide particles as major components, at least one kind of an adhesive polymeric resin and at least one kind of a primary amine resin are contained in the lower layer of the ink receiving layer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a recording medium suitable for recording using water-based ink, a method for producing the recording medium, and an image forming method using the recording medium. In particular, the present invention has a high image density and a clear color tone. The present invention relates to a recording medium capable of forming an image with high resolution and excellent in ink absorbability and an image forming method using the same. Furthermore, the present invention relates to a recording medium excellent in storability of recorded images and an image forming method using the same. Furthermore, the present invention relates to a recording medium excellent in adhesion of an ink receiving layer to a base paper and improved in dusting and an image forming method using the same. Furthermore, the present invention relates to a recording medium excellent in curling prevention and an image forming method using the same.

  The ink jet recording method is a method for recording images, characters, etc. by causing micro droplets of recording liquid (recording liquid) such as ink to fly by various operating principles and adhere to a recording medium such as paper. High-speed, low-noise, easy multi-coloring, large recording pattern flexibility, no need for development, and other features such as copying to printers, copiers, word processors, facsimiles, plotters, etc. Further developments in the output section of information equipment are rapidly spreading. In recent years, high-performance digital cameras, digital videos, scanners, etc. are being offered at low cost, and coupled with the widespread use of personal computers, printers that employ inkjet recording methods for the output of image information obtained from them are extremely suitable. It has come to be used. In such a background, it has been required to easily output an image that is inferior to that of silver salt photography or plate-making multicolor printing by an inkjet recording method.

  In order to satisfy these requirements, improvements have been made to the structure and recording method of the printer itself, such as higher speed recording, higher definition, and full color, and improvements to the structure and characteristics of the recording medium have been actively studied. ing.

  Various types of recording media used for inkjet recording and the like have been proposed. For example, JP-A-52-9074 discloses a recording medium in which a layer having a void mainly composed of a silica pigment having a large specific surface area as a main component is provided as an ink receiving layer in order to improve the ink absorption rate. Japanese Patent Laid-Open No. 63-22997 discloses a recording medium in which the voids of the pigment layer forming the ink receiving layer are adjusted. In Japanese Patent Laid-Open Nos. 55-51583 and 56-157, an amorphous silica powder is used to increase the ink absorption by an ink receiving layer and to obtain print dots having a high print density and no ink bleeding. It is described that is blended. Further, in order to increase ink absorbency, Japanese Patent No. 2686670 and Japanese Patent Application Laid-Open No. 11-1060 describe that the ink receiving layer has a multilayer structure.

  On the other hand, a recording medium comparable to a silver salt-based photograph is required to form an image having excellent dye colorability, high surface glossiness, and high resolution. As a constituent material of an ink receiving layer of a recording medium capable of providing an image comparable to a silver salt photograph, for example, alumina hydrate can be mentioned, and JP-A-7-232473 and JP-A-9-66664. No. 9-99627 and 11-286171.

  Furthermore, recently, the storability of recorded images has been required. A method for improving the storability of recorded images has also been proposed. For example, as a method for improving the storage stability of an image, Japanese Patent Publication No. 6-30951 discloses a recording sheet containing a special cation compound, and Japanese Patent Publication No. 4-28232 includes amino alcohol as a light resistance improver. JP-A-4-34512 and JP-A-11-245504 disclose a recording sheet containing a hindered amine compound as a light resistance improver. Japanese Patent Publication No. 8-13569 discloses the relationship between discoloration when recording images are stored indoors (mainly the phenomenon that black ink turns brown) and discoloration caused by ozone gas. It has been disclosed that silica-based pigments with reduced activity are effective against discoloration of images in the room.

  Most ink jet recording media are provided with an ink receiving layer on a substrate as described above. In this case, there is a problem that the recording medium curls due to the expansion / contraction of the base material itself and the difference in the expansion / contraction ratio between the base material and the ink receiving layer. On the other hand, for example, it is described that a back coat layer is provided as described in JP-A-2001-138628.

  A recording medium capable of forming an image comparable to a silver salt photograph (hereinafter referred to as a photographic recording medium) corresponds to a photo printer to which a large amount of ink is applied at a high speed, and has an excellent dye coloring property and a high surface. In order to achieve glossiness, it has a configuration in which a transparent ink receiving layer is provided with a thickness of several tens of μm or more, or a multilayer configuration. Further, a back coat is often applied to the back surface to prevent curling. In a recording medium having such a complicated configuration, it is particularly difficult to absorb ink and adhere to the substrate (powder falling). In addition, if the layer contains a large amount of additives such as quaternary amine cation agents (ink fixing agents) or light resistance improvers in order to improve image storage stability, the transparency of the receiving layer decreases. There has been a problem that a clear image cannot be formed or the ink absorbability is lowered. Further, the method of modifying the pigment particles themselves for improving the indoor discoloration cannot be applied to such a recording medium. In such a recording medium, when humidity or ink is applied, a difference in expansion and contraction occurs between the base material and the ink receiving layer, and the recording medium curls, resulting in a great obstacle to printer paper feeding. Thus, in order to obtain a photo recording medium having image characteristics, print characteristics, and image fastness, there is a problem to be further solved in terms of balance with the recording characteristics.

  The object of the present invention can be suitably applied to an image forming method using a recording method in which a recording liquid such as an ink jet recording method is attached to a recording medium, and has a high image density, a clear color tone, and a high resolution. It is an object of the present invention to provide a recording medium capable of forming an image and excellent in ink absorbability and an image forming method using the same. Another object of the present invention is to provide a recording medium excellent in storability of recorded images and an image forming method using the same. Furthermore, another object of the present invention is to provide a photographic recording medium from which a print (printed matter) having a texture and image quality as a silver salt photograph can be obtained, and a method for producing the recording medium. An object of the present invention is to provide an image forming method using the above.

  That is, the present invention relates to a recording medium comprising a base material and an ink receiving layer provided on the base material, wherein the ink receiving layer contains at least aluminum oxide particles as a main component, It is a recording medium obtained by applying a coating liquid containing a primary amine resin on a layer and heating and drying. The ink receiving layer is preferably mainly composed of pseudoboehmite or γ-type alumina (γ-alumina) fine particles. Specifically, in the ink receiving layer of the present invention, 70% by mass or more, more preferably 80% by mass or more of the particles constituting the layer is formed of aluminum oxide particles. The molecular weight of the primary amine resin is preferably 10,000 to 500,000, and more preferably 10,000 to 100,000. In the recording medium, the ink receiving layer is wet and the surface thereof is pressed against a heated mirror drum and dried, and the surface gloss of the ink receiving layer is 20% or more when measured at 20 degrees. A recording medium for inkjet recording is preferred.

  In these recording media, the substrate preferably has a surface layer that absorbs the solvent. For example, a material made of hard aluminum oxide having a larger particle diameter and excellent in solvent absorbability, or a surface layer containing barium sulfate and having low air permeability and high density is preferably used.

  According to another aspect of the present invention, there is provided an image forming method for forming an image on a surface having an ink receiving layer on the surface of the recording medium, and a step of receiving recording information; And a step of forming an image by applying a recording liquid accordingly.

  Furthermore, the present invention relates to a method for producing a recording medium having an ink receiving layer on the surface, and after forming a layer containing aluminum oxide particles as a main component on a substrate, further includes a primary amine resin. An application process for applying a coating liquid, a drying process for drying a surface to which the coating liquid has been applied to form a layer, and a method for producing a recording medium characterized by the drying process.

[Action]
According to the present invention, by using the recording medium obtained by the manufacturing method of the present invention, for example, curling can be suppressed even when the environment changes, and printer paper passing performance can be obtained. In addition, even when an inkjet recording image is exhibited in a room for a long time, the occurrence of the above-described various image fading phenomena is suppressed, and it is possible to provide an image with very high robustness. In particular, the present invention can be applied to a photographic recording medium capable of forming a texture and image quality similar to that of a silver salt photograph without impairing its excellent recording characteristics. It became possible to provide by the recording method. Furthermore, by selecting an input system such as a digital camera and using an inkjet recording system as an output, the print (printed material) has excellent image robustness with images that exceed the texture of silver halide photographs and beyond that. ) Can be provided by a simpler and faster process than silver salt photography.

  The recording medium of the present invention has a configuration having a base material and an ink receiving layer provided on the base material, and is a configuration in which an ink receiving layer and a primary amine resin are further applied. The present invention mainly solves each problem that is the object of the present invention by applying the primary amine resin last.

  The present inventors have found that amine compounds that have been conventionally considered to have an adverse effect on the light resistance of images, particularly primary amine resins, and that the above-mentioned fading phenomenon is suppressed, It came to this invention by devising the coating method.

  Hereinafter, embodiments of the present application will be described in more detail.

  The recording medium of the present invention is excellent in the robustness of the recorded image. In particular, even when the recorded image is used for display in a normal indoor environment such as a home or office, the image does not fade. The recording medium of the present invention can also be used for applications that provide recorded images having the same texture and image quality as silver salt photographs. Further, the image forming method of the present invention using such a recording medium can form a high-quality and stable image.

<< Primary amine resin >>
The primary amine-based resin characterizing the present invention is a compound having a primary amino group, and a polymer having a primary amino group in the side chain is preferable. Representative examples include aminomethyl (meth) acrylate, aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, aminoethyl (meth) acrylamide, aminopropyl (meth) acrylamide, allylamine, vinylamine and other homopolymers or other Mention may be made of copolymers with copolymerizable monomers and their salts. Examples of the salt include hydrochloride, sulfate, nitrate and the like. Of these, polyallylamine, polyvinylamine, and salts thereof are particularly preferable. Polyallylamine is prepared as a polymer of monoallylamine, and its production method is described in, for example, Japanese Patent Publication Nos. 2-14364, 2-56361, 2-56362, 2-57082, No. 2-57083 and the like. Polyvinylamine is produced by hydrolyzing polyvinylformamide, polyvinylacetamide or the like, and its production method is described in JP-A-58-23809 and JP-B-5-35163. Yes. What is preferably used in the present invention is a polymer containing only 100% hydrolyzed vinylamine, and a polymer containing a partially hydrolyzed vinylamine structural part, a vinylformamide structural part and / or a vinylacetamide structural part. It is a coalescence.

  In the present invention, the primary molecular weight resin preferably has a molecular weight of 10,000 to 500,000, preferably 10,000 to 100,000.

<Use ratio of primary amine resin>
The proportion of primary amine resin used is preferably 0.01% to 20%, more preferably 0.1% to 10%, and still more preferably 0.2% to 0.2% as a coating liquid from the viewpoint of ink absorbability and image fastness. Within 5% range.

  In the present invention, a method of including a primary amine-based resin in a recording medium is good, and a primary amine is provided on the formed ink-receiving layer, and heat-dried to give the surface of the receiving layer. Is the method.

<Composition of ink receiving layer>
The ink receiving layer is mainly composed of a pigment, a binder, and other additives. Particularly preferable as a photographic recording medium is an ink receiving layer formed mainly of fine particles having an average particle size of 1 μm or less, more preferably 0.5 μm or less, and still more preferably 0.3 μm or less, and has a high gloss on the surface. Therefore, it is possible to form an image with high resolution, high image density, clear color tone and high resolution. As the pigment, aluminum oxide particles are mainly used. As this aluminum oxide, what is usually called a Bayer method, the thing manufactured by baking the aluminum hydroxide obtained by carrying out the hot caustic soda processing of the bauxite which is a natural mineral can be used. In addition to this, it is possible to use a metal aluminum pellet produced by spark discharge in water and then firing the resulting aluminum hydroxide, a method of decomposing an inorganic aluminum salt (such as alum), and the like.

  As for the crystal structure of aluminum oxide, it is known that the transition from kibsite-type and boehmite-type aluminum hydroxide to γ, σ, η, θ, α-type aluminum oxides depends on the heat treatment temperature. Yes. Of course, any of these production methods and crystal structures can be used in the present invention. Of these, boehmite type or γ-type crystal type aluminum oxide (γ-alumina) is preferable in terms of ink absorbability and transparency of the formed layer.

The aluminum oxide preferably has a BET specific surface area in the range of 100 to 160 m ² / g. When the specific surface area exceeds 160 m ² / g, the ink absorbability may be lowered depending on the particle size of the pigment. On the other hand, if the density is less than 100 m ² / g, the color density may decrease due to light scattering.

  In the present invention, the ink receiving layer may contain particles such as conventionally known inorganic pigments and organic pigments in addition to the fine particles. In the present invention, the ink receiving layer is composed of 70% by mass of all particles, more preferably 80% by mass or more of the fine particles.

  Examples of suitable binders include water-soluble polymers and latex. For example, polyvinyl alcohol or a modified product thereof, starch or a modified product thereof, gelatin or a modified product thereof, casein or a modified product thereof, gum arabic, cellulose derivatives such as carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, SBR latex, NBR latex, Conjugated diene copolymer latex such as methyl methacrylate-butadiene copolymer, functional group-modified polymer latex, vinyl copolymer latex such as ethylene vinyl acetate copolymer, polyvinyl pyrrolidone, maleic anhydride or copolymer thereof And acrylic acid ester copolymers. These binders can be used alone or in combination. Additives include dispersants, thickeners, pH adjusters, lubricants, fluidity modifiers, surfactants, antifoaming agents, mold release agents, fluorescent whitening agents, UV absorbers, and oxidation as necessary. An inhibitor or the like can be used.

  The preferred content of the pigment, binder and other additives in the ink receiving layer is such that the pigment is in the range of 50 to 99% by weight, the binder is 1 to 50% by weight, and other additives in the entire receiving layer. Is about 5% or less.

  Further, the mixing ratio of all pigments containing aluminum oxide particles to the binder can be arbitrarily selected from the range of 1: 1 to 100: 1, more preferably 5: 1 to 25: 1 in terms of mass ratio. . By setting the amount of the binder within the above range, the mechanical strength of the ink receiving layer can be further increased, cracking and powder falling off during the formation of the ink receiving layer can be prevented, and a more suitable pore volume can be maintained. It becomes possible.

  The preferable content of aluminum oxide particles in the ink receiving layer is 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and 99% by mass or less.

<Receptive layer coating amount>
The coating amount of the ink receiving layer is 45 g / m ² or less in terms of dry solid content in order to improve the fixability of the colorant component in the recording liquid such as dye and the smoothness of the ink receiving layer. Is preferable, and 10 to 40 g / m ² is more preferable.

<< In the case of having two separate compounds on the receiving layer -Apply separately->>
Composition of coating solution: A primary amine resin is made into an aqueous solution, and the coating solution is prepared. If necessary, the coating solution may be mixed with a water-soluble polymer or latex. Specific examples include those exemplified above. Other additives include dispersants, thickeners, pH adjusters, lubricants, fluidity modifiers, surfactants, antifoaming agents, mold release agents, fluorescent whitening agents, UV absorbers, and antioxidants. An agent or the like can be used. Moreover, a conventionally well-known inorganic pigment and an organic pigment may be included.

Coating amount / impregnation amount: The dry coating amount of the primary amine resin is in the range of 0.01 to 5 g / m ² . If it is applied more than necessary, it may adversely affect recording characteristics such as a decrease in image density and a decrease in ink absorption.

"Base material"
The substrate for forming the ink receiving layer is not particularly limited according to the present invention, and any substrate can be used as long as it can be used as a substrate for a recording medium on which recording liquid is attached. . For example, a paper having a structure having at least a fibrous base mainly composed of wood pulp and filler, such as appropriately sized paper and non-sized paper, and various plastic films such as polyethylene terephthalate film can be used. Further, in order to obtain high glossiness in the present invention, a substrate having a surface layer coated with an inorganic pigment containing at least aluminum oxide or barium sulfate together with a binder on the fibrous substrate is used as a substrate. It is preferable.

<Method for forming receptor layer>
In the recording medium having the ink receiving layer of the present invention, as a method for forming the ink receiving layer on the substrate, a coating liquid containing the above-described material is prepared, and the coating solution is used on the substrate. The method of apply | coating and drying can be used. The coating method is not particularly limited, and commonly used coating techniques such as blade coater, air knife coater, roll coater, curtain coater, bar coater, gravure coater, die coater, spray device, etc. can be used. . As a method for forming an ink receiving layer of a photo recording medium, there is a method in which a coating liquid containing fine particles is coated using the same method as described above, and then the surface is gloss-treated.

《Glossy processing》
As the gloss treatment on the ink-receiving layer surface side of the present invention, a cast method is preferably used in which an object to be treated is brought into pressure contact with a heated mirror drum and dried. As a method for casting, there are a direct method, a gelation method, and a rewet method. Among these methods, the direct method is one in which the surface of the ink receiving layer applied on the support at the time of forming the ink receiving layer is still wet, and the surface of the layer is pressed against a heated mirror drum and dried. In the gelation method, while the ink receiving layer on the support is still wet when the ink receiving layer is formed, the layer is brought into contact with a gelling agent bath to form a gel, and then the surface of this layer is heated. It is pressure-bonded to the mirror drum and dried. Particularly preferred in the present invention is the rewet method. In the rewetting method, the ink-receiving layer-forming coating material is applied onto a substrate, dried by a conventional method, and once formed as a receiving layer, it is treated with hot water again to wet the ink-receiving layer. The surface of the ink receiving layer in the swollen state is pressed against a heated mirror drum and dried. By subjecting the thermal drum to a pressure-bonding treatment in a swollen state, it is possible to impart high gloss to the surface while maintaining the porous structure of the ink receiving layer. In addition, when the ink receiving layer in a wet state is pressed against a mirror drum and dried, moisture is evaporated from the back surface when the thermal drum is pressed and dried in order to re-swell the dried ink receiving layer. Since this method requires only a small amount, this method has few limitations on the substrate to be used, and gloss treatment is possible even when an ink receiving layer is provided on a dense substrate.

  The glossiness on the ink receiving layer side surface of the recording medium according to the present invention thus obtained can be adjusted to have a value of 20% or more in the 20 ° measurement. Is preferable because high quality image formation is possible. The glossiness referred to in the present invention is a value measured according to the method defined in JIS-Z-8741.

"ink"
The ink, which is a recording liquid used in the present invention, contains a dye for forming an image and a liquid medium for dissolving or decomposing the dye as essential components, and various dispersants and surfactants as necessary. It is adjusted by adding a viscosity adjusting agent, a specific resistance adjusting agent, a pH adjusting agent, a fungicide, a recording agent dissolution (or dispersion) stabilizer, and the like.

  Examples of the recording agent used in the ink include direct dyes, acid dyes, basic dyes, reactive dyes, food dyes, disperse dyes, oil-based dyes, various pigments, and the like. be able to. The content of such a dye is determined depending on the type of liquid medium component, characteristics required for the ink, and the like, but is generally used in a ratio of about 0.1 to 20% by mass in the conventional ink. This ratio may be the same in the present invention.

  In the ink used in the present invention, examples of the liquid solvent for dissolving or dispersing the pigment as described above include water or a mixed solvent of water and a water-soluble organic solvent, and particularly preferable are water and a water-soluble solvent. It is a mixed solvent with a water-soluble organic solvent, and contains water-miscible glycols or glycol ethers having an effect of preventing ink drying as a water-soluble organic solvent.

  Examples of the organic solvent that can be used in the ink according to the present invention include alkyl alcohols such as methanol, ethanol, isopropyl alcohol, and n-butanol; amides such as dimethylformamide and dimethylacetamide; ketones such as acetone and acetone alcohol, and keto alcohols. Alkylene glycols such as ethylene glycol, propylene glycol, triethylene glycol, thiodiglycol, diethylene glycol, 1,2,6-hexanetriol, polyethylene glycol; glycerins; (di) ethylene glycol monomethyl (or ethyl) ether, Alkyl ethers of polyhydric alcohols such as triethylene glycol mono (or di) methyl (or ethyl) ether; sulfolane, n-methyl-2-pyrrolidone, 1,3-dithym-2-imidazolide Emissions, and the like, one or more of these can be used.

  The ink according to the present invention is prepared by using the above materials and further adding a surfactant or the like as necessary.

<Inkjet recording method>
The ink jet recording method suitable as the image forming method of the present invention may be any method as long as it can effectively remove the ink from the nozzles and apply the ink to the recording medium as a projectile. The method described in Japanese Patent Publication No. 54-59936 uses the ink jet system that ejects ink from the nozzles by the action force caused by this state change. can do.

  An example of an ink jet recording apparatus suitable for the ink jet recording method of the present invention will be described below. Examples of the configuration of the head, which is the main part of the apparatus, are shown in FIGS. 1 is a cross-sectional view of the head 13 along the ink flow path, and FIG. 2 is a cross-sectional view taken along the line 2-2 ′ of FIG.

  Head 13 is a glass, ceramic, or plastic plate having a groove 14 through which ink passes, and a heat generating head 15 used for thermal recording (the head is shown in the figure, but is not limited thereto). Is obtained. The heat generating head 15 includes a protective film 16 made of silicon oxide or the like, aluminum electrodes 17-1 and 17-2, a heat generating resistor layer 18 made of nichrome or the like, a heat storage layer 19 and a substrate 20 having good heat dissipation such as alumina. It has become more.

  The ink 21 reaches the ejection orifice (fine hole) 22 and forms a meniscus by the pressure P.

  Now, when an electrical signal publication is applied to the electrodes 17-1 and 17-2, the region indicated by n of the heat generating head 15 suddenly generates heat, and bubbles are generated in the ink 21 in contact therewith. Protrudes, and ink 21 is ejected to form recording droplets 24 from the orifice 22 and fly toward the recording sheet 25. FIG. 3 shows an external view of a multi-head in which a large number of heads shown in FIG. 1 are arranged. The multi-head is manufactured by closely contacting a glass plate (not shown) having a multi-groove (not shown) and a heating head (not shown) similar to that described in FIG.

  FIG. 4 shows an example of an ink jet recording apparatus in which such a head is incorporated. In FIG. 4, 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, and forms a cantilever. The blade 61 is disposed at a position adjacent to the recording area by the recording head, and in this example, is held in a form protruding 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 comes into contact with the ejection port surface to perform capping. Further, 63 is an ink absorber provided adjacent to the blade 61 and, like the blade 61, is held in a form protruding in the moving path of the recording head. The blade 61, the cap 62, and the absorber 63 constitute a discharge recovery portion 64, and the blade 61 and the absorber 63 remove moisture, dust, and the like from the ink discharge port surface.

  65 has a discharge energy generation means, and a recording head for recording by discharging ink onto a recording medium facing the discharge port surface on which the discharge port is arranged. 66 has a recording head 65 mounted thereon to move the recording head 65. Carriage for performing. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown). As a result, the carriage 66 can move along the guide shaft 67, and the recording area and its adjacent area can be moved by the recording head 65.

  51 is a paper feed section for inserting a recording medium, and 52 is a paper feed roller driven by a motor (not shown). With these configurations, the recording medium is fed to a position facing the discharge port surface of the recording head, and is discharged through the discharge roller 53 as recording progresses.

  In the above configuration, when the recording head 65 returns to the home position due to the end of recording or the like, the cap 62 of the head recovery unit 64 is retracted from the moving path of the recording head 65, but the blade 61 protrudes into the moving path. As a result, the discharge port surface of the recording head 65 is wiped. When the cap 62 is in contact with the protruding surface of the recording head 65 for capping, the cap 62 moves so as to protrude 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 position as that at the time of wiping described above. As a result, the ejection port surface of the recording head 65 is wiped even during this movement.

  The above-mentioned movement of the recording head to the home position is not only at the end of recording or at the time of ejection recovery, but also to the home position adjacent to the recording area at a predetermined interval while the recording head moves through the recording area for recording. Then, the wiping is performed with this movement.

  Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples.

[Synthesis example of primary amine resin]
・ Synthesis example of 2-aminoethyl methacrylate polymer (C-1) 100 parts of 60% isopropyl alcohol aqueous solution was charged into a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube. Was replaced with nitrogen, and then heated slowly to reflux. Next, 25 parts of 2-aminoethyl methacrylate hydrochloride (manufactured by Aldrich) and 100 parts of a 60% isopropyl alcohol aqueous solution containing 0.4 part of 2,2′azobisisobutylnitrile were added dropwise over 2 hours for polymerization. Thereafter, the reaction solution was heated to reflux for 3 hours, diluted by adding 100 parts of water, isopropyl alcohol was distilled off, and the concentration was adjusted to obtain an aqueous solution having a solid content of 15%. The molecular weight of the obtained polymer was Mw 45,000 using polyethylene glycol as a standard substance.

・ Synthesis example of polyallylamine salt (C-2) According to the method described in the example of JP-B-2-57083, after adjusting polyallylamine hydrochloride from monoallylamine, the concentration was adjusted to obtain a 10% by mass aqueous solution. Polyvinylamine was obtained. The molecular weight of the obtained polymer was 10,000.

・ Synthesis example of polyvinylamine salt (C-3) According to the method described in the example of Japanese Patent Publication No. 5-35163, N-vinylformamide is polymerized and then hydrolyzed, and the concentration is adjusted to 5 mass. % Aqueous solution of polyvinylamine was obtained. The solution was adjusted to pH = 7 with concentrated hydrochloric acid. The polymer obtained had a hydrolysis rate of 59% by mass and a molecular weight of 70,000.

[Examples of comparative compounds]
・ Quaternary ammonium compounds (C-4)
As a commercially available compound having a quaternary ammonium base, a dimethyldiallylammonium chloride polymer described in JP-A-59-20696 was used as a comparative compound.

[Production example of alumina hydrate (pseudo boehmite)]
Aluminum octoxide was synthesized by the method described in US Pat. No. 4,242,271 and US Pat. No. 4,420,870, and then hydrolyzed to produce an aluminum slurry. Pure water was added to the alumina slurry so that the solid content was 5% by weight. Next, this was heated to 80 ° C. and subjected to aging reaction for 10 hours, and then the alumina dispersion was spray-dried to obtain alumina hydrate A. Next, this alumina hydrate A was mixed and dispersed in pure water, and the pH was adjusted to 4 with hydrochloric acid. The dispersion was heated to 90 ° C., pH was adjusted to 10 using caustic soda, and the mixture was stirred for 6 hours. Then, it cooled to room temperature and adjusted pH to 8, and obtained the alumina dispersion liquid. The alumina dispersion was desalted and peptized, and then dried by spray drying to obtain alumina hydrate B. When the alumina hydrate B was measured by X-ray diffraction, it had a pseudo boehmite structure. This alumina hydrate B was again mixed with pure water so that the solid content was 25% by weight, and 2% acetic acid was further added to the solid content to obtain an alumina dispersion.

[Production example of γ-alumina]
Aluminum octoxide was synthesized by the method described in US Pat. Nos. 4,242,271 and 4202870, and then hydrolyzed to produce an alumina slurry. Thereafter, post-treatment such as drying was performed to obtain a pseudo boehmite powder. This was baked in an oven at 500 ° C. for 2 hours to obtain aluminum oxide particles having a γ-type crystal structure (hereinafter: γ-alumina). The median particle size distribution at this time was 20 μm. This γ-alumina was dispersed in pure water at a concentration of 20% by mass using acetic acid as a dispersant. Then, after processing for 40 hours with a ball mill, coarse particles were removed by centrifugal separation to obtain a γ-alumina-treated product. The average particle size distribution at this time was 0.25 μm.

[Example of recording medium preparation: ink-receiving layer composition]
(Coating liquid adjustment example)
Completely saponified polyvinyl alcohol (trade name: PVA117 manufactured by Kuraray Co., Ltd.) was dissolved in ion-exchanged water to obtain a 9% by mass solution. The pseudo boehmite dispersion prepared in the above production example and the polyvinyl alcohol solution were mixed and stirred so that the alumina solid content and the polyvinyl alcohol solid content were in a mass ratio of 10: 1 to obtain a dispersion.

(Create recording media)
Each coating solution prepared as described above was applied to a baryta layer of a base material (Beck smoothness 420 seconds, whiteness 89%) having barium sulfate and γ-alumina with a dry thickness of 30 g / m ² by die coating. The base material at this time is a dry weight of 30 g / m ² on a fibrous base material having a basis weight of 135 g / m ² and a Steecht sizing degree of 200 seconds, consisting of 10 parts by weight of gelatin per 100 parts by weight of barium sulfate. In this way, coating is performed and calendar processing is performed. In this way, a layer for forming an ink receiving layer was formed on the substrate having the baryta layer. Using a rewetting cast coater on the surface of the above-mentioned receptor layer forming layer, a rewetting cast treatment using hot water (80 ° C.) is performed, and the recording media 1 to 12 of the present invention and the recording medium for comparison 13 ~ 19 was obtained. The recording surfaces of the recording media thus prepared had high surface glossiness.

  The recording medium obtained above was evaluated by the following method. The results are shown in Table 3.

(Robustness test 1)
Various image fastness tests were performed according to the following methods (1) to (3) using the recorded material prepared by the following method.

  -Creation of recorded matter: Using a photo printer (trade name: BJ-F 870 manufactured by Canon) using an inkjet method, black, cyan, magenta, yellow, composite black, Leaf green, flesh and sky solid patches were printed, and patches of each color OD 1.0 were used for the test.

  Evaluation method of light resistance and gas resistance: The image density before the test and the image density after the test of the above recorded matter were measured using a spectrophotometer / Spectrino (manufactured by Gretag Macbeth). The light resistance and gas resistance evaluation were determined based on the criteria described below, and the results are shown in Table 3.

Test method (1) Light resistance test 1
According to the following test conditions, a light resistance exposure test was performed using a xenon fade meter. This test is an image fastness test that takes into account the effect of sunlight through windows.

・ Test conditions Irradiation quantity: 70 klux
Test time: 100 hours Temperature and humidity conditions in the test chamber: 24 ° C / 60% RH
Filter: (Outer) Soda lime, (Inner) Borosilicate ・ Light resistance evaluation
With reference to the standard of ISO 10977 (1993), the light resistance was evaluated as follows from the concentration residual rate data after the light resistance exposure test.

A: Density residual ratio is 90% or more and the difference in density residual ratio of each constituent color is within 5% in the composite color B: The density residual ratio is 80% to 89%, and in the composite color Difference in density residual ratio of constituent colors within 10% C: Concentration residual ratio less than 80%, or in composite color, each constituent color difference is 15% or more (2) Light resistance test 2
According to the following test conditions, a light exposure test was conducted using a fluorescent light resistance tester. This test is an image fastness test considering the influence of fluorescent light in the room.

・ Test conditions Irradiation quantity: 70 klux
Test time: 240 hours Temperature and humidity conditions in the test layer: 24 ° C / 60% RH
Filter: Soda limeLight resistance evaluation
With reference to the standard of ISO 10977 (1993), the light resistance was evaluated as follows from the concentration residual rate data after the light resistance exposure test.

A: Density residual ratio is 90% or more and the difference in density residual ratio of each constituent color is within 5% in the composite color B: The density residual ratio is 80% to 89%, and in the composite color Concentration residual ratio difference of constituent colors is within 10% C: Concentration residual ratio is less than 80%, or in composite color, each constituent color difference is 15% or more (3) Gas resistance test According to the test conditions (ANSI / ISA-S 71.04-1985), a gas exposure test was performed using a gas corrosion tester. This test is an image fastness test considering the influence of various gases in the room.

Test conditions Exposure gas composition: H ₂ S 10 ppb, SO ₂ 100 ppb, NO ₂ 125 ppb, Cl _{2 2} ppb, O ₃ 25 ppb
Test time: 168 hours Temperature and humidity conditions in the test layer: 24 ° C / 60% RH
-Gas resistance evaluation The gas resistance was evaluated as follows based on the residual concentration data after the light exposure test and visual judgment.

A: Concentration residual rate is 80% or more, and no change in color tone is observed compared to before the test B: Concentration residual rate is 80% to 70%, and the color tone slightly changes compared to before the test C: Concentration remaining rate is less than 70%, clearly different color than before the test
(Robustness test 2: Yellowing test)
Test Method and Evaluation Method An unprinted recording medium was used for the test. The recording medium was left in the following environment, and the colors of the recording surfaces before and after the test were compared. The results are shown in Table 3.

Test conditions/
Test layer temperature and humidity conditions: 50 ℃, 80% RH
Test time: 240 hours

It is a longitudinal cross-sectional view of the head part of an inkjet recording device. It is a cross-sectional view of the head part of an inkjet recording device. FIG. 2 is an external perspective view of a head in which the head shown in FIG. It is a perspective view which shows an example of an inkjet recording device.

Explanation of symbols

13 heads
14 groove
15 Heat generation head
16 Protective film
17-1, 17-2 electrodes
18 Heating resistor layer
19 Thermal storage layer
20 substrates
21 ink
22 Orifice
24 recording droplets
25 Recording sheet
51 Feeder
52 Paper feed roller
53 Paper ejection roller
61 Wiping parts
62 cap
63 Ink absorber
64 Discharge recovery section
65 Recording head
66 Carriage
67 Guide shaft
68 motor
69 belt

Claims (2)

A recording medium comprising a substrate and an ink receiving layer provided on the substrate;
In the recording medium, wherein the ink receiving layer has at least two layers and the outermost layer contains aluminum oxide particles as a main component, at least one kind of an adhesive polymer resin is provided under the ink receiving layer. And at least one primary amine resin. A method for producing a recording medium according to claim 1,
a) providing an ink-receiving layer lower layer containing the primary amine;
2. The method for producing a recording medium according to claim 1, further comprising a step of b) providing an outermost layer of an ink receiving layer containing aluminum oxide particles as a main component.

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