JP2007076215A - Method for manufacturing inkjet recording sheet and method for manufacturing coated sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure that no defects such as tiered cracks, wind ripple, run and crazing are not generated, without preparing many different kinds of base materials containing different amounts of gelatinizing agents. <P>SOLUTION: This method manufactures an inkjet recording sheet using a base material 11 with a layer containing a gelatinizing agent formed on one surface of a support, a coating liquid 12 containing a resin with gelation properties which becomes a gel by the gelatinizing agent, and a coating liquid 13 and 14 for forming an ink receptive layer containing the resin with gelation properties which becomes a gel by a fine particle and the gelatinizing agent. In addition, the coating liquid 12 containing the resin with gelation properties is applied to the surface of the layer containing the gelatinizing agent of the base material 11 and the coating liquid 13 and 14 for forming the ink receptive layer is applied to the surface of the applied coating liquid 12 containing the resin with gelation properties. Thus the amount of the gelatinizing agent permeating the coating liquid 13 and 14 for forming the ink receptive layer from the layer containing the gelatinizing agent of the base material 11, can be adjusted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a recording sheet applied to an ink jet recording system. Moreover, it is related with the method of manufacturing the coating sheet which has a coating layer.

  Ink jet recording method in which water-based ink is ejected from a fine nozzle toward a recording sheet and an image is formed on the recording surface of the sheet has less noise during recording, and it is easy to form a full-color image. It is widely used in terminal printers, facsimiles, plotters, form printing, and the like due to the fact that high-speed recording is possible and the recording cost is lower than other printing apparatuses.

  As a recording sheet suitable for the ink jet recording method, an ink jet recording sheet having an ink receiving layer is widely used. Ink jet recording sheets are required to have advanced characteristics due to the rapid spread of printers, high definition and high speed, and the advent of digital cameras. For example, there is a strong demand for ink jet recording sheets having ink absorbability, gloss and crack resistance comparable to silver salt photography.

Patent Document 1 proposes a method of manufacturing an ink jet recording sheet that satisfies the above requirements. Specifically, a base material in which boric acid or a boron compound as a gelling agent is coated on a support to form a gelling agent-containing layer is prepared, and fine particles are formed on the gelling agent-containing layer of the base material. Then, an ink receiving layer-containing coating liquid containing a water-soluble resin is applied to form an ink receiving layer to obtain an ink jet recording sheet. In this method, when the ink-receiving layer-forming coating liquid is applied onto the gelling agent-containing layer, the gelling agent in the gelling-agent-containing layer penetrates into the ink-receiving layer-forming coating liquid and penetrates therethrough. The water-soluble resin in the ink receiving layer can be gelled by the gelling agent. As a result, it is possible to obtain an ink receiving layer having improved gloss and crack prevention properties while maintaining ink absorbability.
JP 2001-246832 A

By the way, in the ink jet recording sheet, since the thickness and components of the ink receiving layer are usually changed according to the application, when the ink receiving layer is gelled with a gelling agent, the thickness of the ink receiving layer is It is necessary to change the amount of gelling agent according to the composition of the sheath. If the amount of the gelling agent is too large, it may gel suddenly and cause a step crack on the surface of the ink receiving layer. If the amount of the gelling agent is too small, it will not be sufficiently gelled. Defects such as wind ripples, flow, and cracks may occur on the surface of the ink receiving layer. Therefore, in manufacturing an inkjet recording sheet using a base material having a gelling agent-containing layer, prepare base materials with different amounts of gelling agent depending on the thickness of the ink receiving layer and the composition of the constituent components. I had to.
The present invention has been made in view of the above circumstances, and without having to prepare a large number of base materials with different amounts of gelling agent, it does not cause defects such as step cracks, wind ripples, flow, cracks, and the like. It is an object of the present invention to provide a method for producing an ink jet recording sheet and a method for producing a coated sheet that can efficiently form various ink receiving layers having different constituent components.

The method for producing an inkjet recording sheet of the present invention includes a base material on which a gelling agent-containing layer containing a gelling agent is formed on one side of a support, and a gelling resin that gels with the gelling agent. A method for producing an ink jet recording sheet by using a gelling resin-containing coating liquid, and a coating liquid for forming an ink receiving layer containing a fine particle and a gelling resin that gels with the gelling agent,
By coating the gelling resin-containing coating liquid on the gelling agent-containing layer of the substrate, and coating the ink-receiving layer forming coating liquid on the coated gelling resin-containing coating liquid, The amount of the gelling agent that permeates the coating liquid for forming the ink receiving layer from the gelling agent-containing layer of the substrate is adjusted.
In the method for producing an inkjet recording sheet of the present invention, by adjusting the gelling resin concentration in the gelling resin-containing coating liquid and / or the wet coating amount of the gelling resin-containing coating liquid, It is preferable to adjust the amount of the gelling agent penetrating from the gelling agent-containing layer of the base material into the ink receiving layer forming coating solution.
In the method for producing an inkjet recording sheet of the present invention, the gelling agent is preferably a crosslinking agent.
Furthermore, it is preferable that the crosslinking agent is a boron-containing compound.
In the method for producing an ink jet recording sheet of the present invention, it is preferable that the gelling resin-containing coating liquid and the ink-receiving layer-forming coating liquid are simultaneously subjected to multilayer coating.
In the method for producing an inkjet recording sheet of the present invention, a gelling resin-containing coating liquid and a plurality of ink-receiving layer forming coating liquids can be simultaneously applied in multiple layers.
The method for producing a coated sheet of the present invention includes a base material on which a gelling agent-containing layer containing a gelling agent is formed on one side of a support, and a gel containing a gelling resin that gels with the gelling agent. A method for producing a coating sheet with a coating liquid for adjusting the coating and a coating liquid for forming a coating layer,
By coating the gelling adjustment coating liquid on the gelling agent-containing layer of the base material, and applying the coating layer forming coating liquid on the coated gelling adjustment coating liquid, The amount of the gelling agent penetrating from the gelling agent-containing layer into the coating layer forming coating liquid is adjusted.

  According to the method for manufacturing an inkjet recording sheet and the method for manufacturing a coated sheet of the present invention, defects such as step cracks, wind ripples, flow, and cracks can be obtained without preparing a large number of base materials having different amounts of gelling agent. Without the occurrence, various ink receiving layers having different thicknesses and constituent components can be formed efficiently.

The method for producing an inkjet recording sheet of the present invention includes a base material on which a gelling agent-containing layer containing a gelling agent is formed on one side of a support, and a gelling resin that gels with the gelling agent. This is a method for producing an ink jet recording sheet using a gelling resin-containing coating liquid and a coating liquid for forming an ink receiving layer containing fine particles and a gelling resin that gels with the gelling agent. Furthermore, in the method for producing an inkjet recording sheet of the present invention, a gelling resin-containing coating liquid is applied on the gelling agent-containing layer of the substrate, and the gelling resin-containing coating liquid is applied. In this method, the amount of the gelling agent penetrating from the gelling agent-containing layer of the base material into the ink receiving layer forming coating solution is adjusted by applying the ink receiving layer forming coating solution.
Hereafter, the structure of the manufacturing method of the inkjet recording sheet of this invention is demonstrated in detail.

[Base material]
The base material has a gelling agent-containing layer containing a gelling agent formed on one side of the support.
As the support constituting the substrate, either a gas permeable support or a gas impermeable support can be used, but a gas impermeable support is preferred. This is because when a non-air-permeable support is used, it is possible to suppress a so-called cockling defect that the recording sheet stretches and undulates due to the influence of a solvent such as moisture contained in the ink. However, in the case of a non-permeable support, the ink cannot be absorbed by the support, and therefore it is necessary that the ink receiving layer has a sufficient absorbing power.
Further, the support may be transparent or opaque.

  Specific examples of the support include films such as cellophane, polyethylene, polypropylene, soft polyvinyl chloride, hard polyvinyl chloride, polyester, fine paper, art paper, coated paper, cast coated paper, foil paper, kraft paper, Examples include polyolefin resin-coated paper, impregnated paper, vapor-deposited paper, paper such as water-soluble paper, sheets of metal foil, synthetic paper, etc. Coated paper, baryta paper, photographic paper base paper, synthetic paper, and polyolefin resin-coated paper are preferred. Among them, synthetic paper and polyethylene resin-coated paper are preferable. In particular, a support made of polyethylene resin-coated paper kneaded with titanium oxide, so-called RC paper, is particularly preferably used because the finished appearance is equivalent to that of photographic printing paper. It is done. In addition, when RC paper is used as the support, the effects of the present invention are particularly exerted.

  In the polyethylene resin-coated paper, the thickness of the polyethylene layer is preferably 3 to 50 μm, and more preferably 5 to 30 μm. When the thickness of the polyethylene layer is less than 3 μm, defects such as holes in the polyethylene resin are likely to increase during resin coating, the thickness is often difficult to control, and smoothness is difficult to obtain. On the other hand, if it exceeds 50 μm, the resulting effect is small and uneconomical for the increase in cost.

As the gelling agent contained in the gelling agent-containing layer constituting the base material, various known ones that gel, in particular, crosslink, the gelling resin in the gelling resin-containing coating liquid and the ink receiving layer forming coating liquid Any gelling agent can be used.
For example, as the gelling agent when the gelling resin is polyvinyl alcohol or various modified polyvinyl alcohols, aldehyde-based crosslinking agents such as glyoxal, epoxy-based crosslinking agents such as ethylene glycol diglycidyl ether, bisvinylsulfonylmethyl ether, etc. And vinyl-containing crosslinking agents, boron-containing compounds such as boric acid and borax, zirconium compounds, aluminum compounds, chromium compounds, and the like. Among these, since thickening or gelation is quick, a crosslinking agent is preferable and a boron-containing compound is more preferable.

  Here, the boron-containing compound is an oxygen acid having a boron atom as a central atom and a salt thereof. Specific examples include orthoboric acid, metaboric acid, hypoboric acid, tetraboric acid, pentaboric acid, and sodium, potassium and ammonium salts thereof. Among these, orthoboric acid and disodium tetraborate are preferably used because they have an effect of appropriately thickening the coating solution.

  After coating the gelling resin-containing coating liquid and the ink receiving layer forming coating liquid on the substrate, the gelling agent in the gelling agent-containing layer is converted into the gelling resin-containing coating liquid and the ink receiving layer. Since it transfers to the forming coating liquid, the gelling agent-containing layer may disappear. Therefore, the base material in the ink jet recording sheet may be only the support.

[Gelable resin-containing coating liquid]
The gelling resin-containing coating liquid is a coating liquid in which a gelling resin is contained in water and / or an organic solvent.
Here, the gelling resin is gelled by a gelling agent. Among gelling resins, a water-soluble resin is preferable in that water can be used as a dispersion medium. Examples of the water-soluble resin include polyvinyl alcohol, cation-modified polyvinyl alcohol, silyl-modified polyvinyl alcohol, polyvinyl acetal, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, casein, soy protein, synthetic proteins, starch, polypropylene oxide, polyethylene glycol, polyvinyl ether. , Polyvinyl acrylamide and polyvinyl pyrrolidone.

  The gelling resin-containing coating liquid may contain other resins other than the gelling resin. In addition, the above gelling agents, various dispersants, surfactants, thickeners, antifoaming agents, colorants, antistatic agents, preservatives, ultraviolet absorbers, preservatives, fluorescent whitening agents, and the like. An auxiliary agent may be included.

The gelling resin-containing coating liquid can adjust the amount of the gelling agent that penetrates from the gelling agent-containing layer of the base material into the ink-receiving layer-forming coating liquid. Here, the gelling resin-containing coating liquid can adjust the penetration amount of the gelling agent before the gelling agent in the gelling agent-containing layer penetrates into the ink-receiving layer forming coating liquid. This is because it is used for the gelation of the gelling resin in the coating liquid containing the conductive resin, or the time for the gelling agent to reach the coating liquid for forming the ink receiving layer is delayed by the gelling agent-containing layer. The amount of penetration of the gelling agent can be adjusted when the time to reach the ink receiving layer forming coating solution is delayed because all gelling agents are dried before reaching the ink receiving layer forming coating solution. This is because it is difficult to move the gelling agent when finished.
As a method of adjusting the penetration amount of the gelling agent from the base material to the ink receiving layer forming coating liquid, a method of adjusting the dry coating amount of the gelling resin in the gelling resin-containing coating liquid, specifically For this, a method of adjusting the gelling resin concentration and / or the wet coating amount of the gelling resin is preferable. Further, the resin concentration other than the gelling resin may be adjusted.
In addition, the coating amount of the gelling resin-containing coating solution may be appropriately changed in advance according to the ink receiving layer forming coating solution, or the coating amount may be adjusted from the quality of the obtained product. May be.

[Ink-receiving layer-forming coating solution]
The ink receiving layer forming coating solution is a coating solution in which fine particles and a gelling resin are contained in water and / or an organic solvent.
As fine particles, for example, amorphous silica (including synthetic amorphous silica produced by a wet method and a dry method, and cation-modified silica such as alumina), amorphous silica and a cationic compound are mixed and aggregated. Amorphous silica-cationic compound aggregate particles, kaolin, clay, calcined clay, zinc oxide, tin oxide, titanium oxide, magnesium sulfate, aluminum hydroxide, alumina and alumina hydrate, calcium carbonate, satin Examples thereof include white, aluminum silicate, smectite, zeolite, magnesium silicate, magnesium carbonate, magnesium oxide, diatomaceous earth, styrene-based plastic pigment, urea resin-based plastic pigment, and benzoguanamine-based plastic pigment. Among these, amorphous silica and an amorphous silica-cationic compound aggregate obtained by mixing and aggregating amorphous silica and a cationic compound from the viewpoint of easy balance between glossiness and ink absorbability It is preferable to use particles, aluminosilicate, alumina, or alumina hydrate.
The average secondary particle diameter of the fine particles is preferably 0.7 μm or less, particularly from the viewpoint of gloss.

Examples of the gelling resin contained in the ink-receiving layer-forming coating liquid include those that gel with the gelling agent, and specifically, the same resin as that contained in the gelling resin-containing coating liquid. Among them, polyvinyl alcohol is preferable from the viewpoint of ink absorbability, water resistance, and prevention of cracks. Furthermore, the polyvinyl alcohol preferably has a polymerization degree of 3000 to 5000. If the degree of polymerization is less than 3000, the resulting ink-receiving layer tends to have insufficient water resistance, and those exceeding 5000 are practically difficult to obtain. The resin in the ink-receiving layer-forming coating solution may be the same as or different from the resin in the gelling resin-containing coating solution.
In the ink-receiving layer-forming coating solution, the gelling resin is used in an amount of preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass with respect to 100 parts by mass of the fine particles.

Examples of the ink-receiving layer-forming coating liquid include water-dispersible resins (for example, styrene-butadiene copolymer, conjugated diene polymer latex of methyl methacrylate-butadiene copolymer, acrylic polymer latex, styrene-acetic acid). Various adhesives generally used in the field of coated paper, such as a vinyl copolymer latex such as a vinyl copolymer) may be contained.
The ink receiving layer forming coating liquid may contain a cationic compound. Examples of the cationic compound include polyalkylene polyamines such as polyethylene amine and polypropylene polyamine, or derivatives thereof, acrylic resins having a tertiary amino group or a quaternary ammonium group, and diacrylamine. As content of a cationic compound, it is preferable that it is 1-30 mass parts with respect to 100 mass parts of microparticles | fine-particles, and it is more preferable that it is 5-20 mass parts.

  Furthermore, the coating liquid for forming the ink receiving layer includes various dispersants, surfactants, thickeners, antifoaming agents, colorants, antistatic agents, preservatives, ultraviolet absorbers, storage stability improvers, fluorescent whitening agents. Various auxiliaries such as an agent may be included.

[Coating method]
The coating method for the gelling resin-containing coating liquid and the ink-receiving layer-forming coating liquid is not particularly limited, but it is excellent in production efficiency and can reduce the space of the coating apparatus. A method in which a resin-containing coating solution and an ink-receiving layer-forming coating solution are simultaneously applied by multilayer coating is preferred. As used herein, simultaneous multilayer coating is a method of forming a multilayer structure by simultaneously applying two or more coating liquids to a substrate.
Examples of the coating apparatus applied when performing simultaneous multilayer coating include a slide bead coater and a curtain coater.

Hereinafter, an embodiment will be described in which a gelling resin-containing coating liquid and an ink-receiving layer-forming coating liquid are applied simultaneously on a base material by a slide bead coater.
FIG. 1 shows a slide bead coater that performs simultaneous multilayer coating. The slide bead coater 1 includes a backup roll 10 that winds and transports a base material 11 around a circumferential surface, and a slide head 20 that is adjacent to the backup roll 10 and has a slide surface 21 that is inclined downward toward the backup roll 10. It comprises.
Further, a supply flow for supplying the gelling resin-containing coating liquid 12, the ink receiving layer forming coating liquid (A liquid) 13, and the ink receiving layer forming coating liquid (B liquid) 14 to the slide head 20. Manifolds 23a, 23b communicating with the passages 22a, 22b, 23c and the supply passages 22a, 22b, 22c, respectively, expand the gelling resin-containing coating liquid 12 and the ink receiving layer forming coating liquids 13, 14 to the coating width. , 23c, and slots 24a, 24b, 24c communicating with the manifolds 23a, 23b, 23c and opening at the slide surface 21 are formed. The slot 24b opens at a position higher than the slot 24a, and the slot 24c opens at a position higher than the slot 24b.

In simultaneous multilayer coating using the slide beat coater 1, the gelling agent-containing layer (not shown) of the base material 11 is disposed so as to face outward, and is formed on the lower side of the peripheral surface of the rotating backup roll 10. The material 11 is brought into contact. Then, the backup roll 10 is rotated, and the base material 11 is conveyed while being wound from the lower side to the upper side of the peripheral surface of the backup roll 10.
Further, a predetermined amount of the gelling resin-containing coating liquid 12 is supplied to the supply flow path 22a of the slide head 20, and flows out from the slot 24a to the slide surface 21 through the manifold 23a. At the same time, a predetermined amount of the ink receiving layer forming coating liquid (A liquid) 13 is supplied to the supply flow path 22b and flows out from the slot 24b to the slide surface 21 through the manifold 23b, thereby forming the ink receiving layer in the supply flow path 22c. A predetermined amount of the coating liquid (B liquid) 14 is supplied and flows out from the slot 24c to the slide surface 21 through the manifold 23c. At that time, on the slide surface 21, the flow of the ink-receiving layer-forming coating liquids 13 and 14 sequentially overlaps the flow of the gelling resin-containing coating liquid 12 to form a multilayer flow. Then, the gelling resin-containing coating liquid 12 and the ink receiving layer forming coating liquids 13 and 14 that have flowed out to the slide surface 21 flow down along the slide surface 21 in a multi-layered flow, and the substrate 11 on the backup roll 10 It adheres in contact with the gelling agent-containing layer. Here, since the base material 11 is conveyed along with the rotation of the backup roll 10, the positions where the gelling resin-containing coating liquid 12 and the ink receiving layer forming coating liquids 13 and 14 adhere continuously shift, The gelling resin-containing coating liquid 12 and the ink-receiving layer-forming coating liquids 13 and 14 are coated on the gelling agent-containing layer of the substrate 11 in a film form. Thereafter, the gelling agent penetrates from the gelling agent-containing layer into the gelling resin-containing coating liquid 12 and the ink receiving layer forming coating liquids 13 and 14 to gel the gelling resin. Then, through a drying process, an ink jet recording sheet 30 (see FIG. 2) in which the gelling resin-containing layer 32 and the ink receiving layers 33 and 34 are sequentially formed on the substrate 11 is obtained. In this production method, the gelling agent-containing layer disappears because the gelling agent in the gelling agent-containing layer penetrates into the gelling resin-containing coating solution 12 and the ink-receiving layer-forming coating solution 13. Sometimes. Therefore, in the inkjet recording sheet 30, the base material 11 may be formed only of the support.

As in the manufacturing method using the slide bead coater 1, in the case of simultaneous multilayer coating, the viscosity of the gelling resin-containing coating liquid and the ink receiving layer forming coating liquid is important. Specifically, The viscosity of the gelling resin-containing coating solution is preferably 20 to 120 mPa · s, and the viscosity of the ink receiving layer forming coating solution is preferably 20 to 300 mPa · s. Further, the viscosity of the gelling resin-containing coating liquid is preferably 5 mPa · s or more larger than the viscosity of the ink receiving layer forming coating liquid. If the viscosity is in such a range, the interface between the two coating liquids is unlikely to be disturbed, so that stable multilayer coating can be achieved.
In addition, the viscosity here is a value measured at 20 ° C. with a B-type viscometer. Although the temperature at the time of multilayer coating is often 15 to 50 ° C., the tendency of the viscosity measured at 20 ° C. is the same as the tendency of the viscosity in the temperature range at the time of multilayer coating.

Moreover, as a coating method of the gelling resin-containing coating liquid and the ink receiving layer forming coating liquid, a so-called wet-on-wet coating method in which each coating liquid is sequentially applied without being dried can be employed. That is, after applying the gelling resin-containing coating liquid on the substrate, the ink-receiving layer-forming coating liquid is directly applied onto the coated gelling resin-containing coating liquid without drying. Can be taken.
As a coating apparatus in the wet-on-wet coating method, for example, a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a rod blade coater, a lip coater, a die coater, a curtain coater, a slide bead coater, or the like can be applied.

The coating of the ink receiving layer forming coating solution may be one layer or two or more layers, and is appropriately selected according to the purpose. In the case of two or more layers, the ink-receiving layer-forming coating liquids may have the same formulation or different formulations. In addition, the upper and lower layers may contain cationic compounds so as to be different from each other, and various auxiliary agents may be contained in any one layer. The gelling resin-containing coating liquid and the plurality of ink-receiving layer forming coating liquids can be multilayered simultaneously.
Further, the coating amount of the ink receiving layer forming coating liquid is appropriately selected according to the purpose.

  In the method for producing an inkjet recording sheet of the present invention, the gelling resin-containing coating liquid adjusts the penetration amount of the gelling agent from the gelling agent-containing layer of the base material into the ink-receiving layer-forming coating liquid. The gelation degree of the gelling resin in the ink receiving layer forming coating liquid can be easily adjusted. Therefore, without preparing a large number of base materials with different amounts of gelling agent, the degree of gelation (crosslinking density) of the ink receiving layer is adjusted, and defects such as step cracks, wind ripples, flow, and cracks do not occur. Various ink receiving layers having different thicknesses and components can be formed efficiently.

The present invention can be applied not only to the manufacture of inkjet recording sheets but also to the manufacture of coated sheets such as thermal transfer sheets and printing sheets. That is, in the method for producing a coating sheet of the present invention, the gelling adjustment coating liquid is applied on the gelling agent-containing layer of the substrate, and the coating layer is applied on the coated gelling adjustment coating liquid. By applying the forming coating solution, the amount of the gelling agent penetrating from the gelling agent-containing layer of the base material into the coating layer forming coating solution is adjusted. Here, the gelation adjusting coating solution and the coating layer forming coating solution both contain a gelling resin, and the gelation adjusting coating solution and the coating layer forming coating solution are the same. However, in order to give the coating layer a function, it is preferable that the coating layer forming coating solution contains a component not included in the gelation adjusting coating solution.
According to the method for producing a coated sheet, the same effects as those of the method for producing an inkjet recording sheet can be exhibited.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples. Further, “parts” and “%” in the examples are “parts by mass” and “mass%”, respectively, unless otherwise specified.

(Base material)
[Manufacture of paper support]
Coniferous bleached kraft pulp (NBKP) beaten to CSF (JIS P-8121) to 250 ml and hardwood bleached kraft pulp (LBKP) beaten to CSF to 250 ml are mixed at a mass ratio of 2: 8, and the concentration is 0. A 5% pulp slurry was prepared. In this pulp slurry, cationized starch 2.0%, alkyl ketene dimer 0.4%, anionized polyacrylamide 0.1% and polyamide polyamine epichlorohydrin 0.7% are added to the pulp dry mass, And dispersed with stirring.
The pulp slurry having the above composition was made with a long net machine, and a base paper having a basis weight of 180 g / m ² and a density of 1.0 g / cm ³ was produced through a dryer, a size press, and a machine calendar. The size press solution used in the size press step is prepared by mixing carboxyl-modified polyvinyl alcohol and sodium chloride at a mass ratio of 2: 1, adding this to water, dissolving by heating, and adjusting the concentration to 5%. . Then, this size press solution was applied to both sides of the paper in a total of 25 ml / m ² to obtain a paper support (air permeability: 300 seconds).

[Manufacture of resin-coated paper]
After the corona discharge treatment is performed on both sides of the paper support, the following polyolefin resin composition 1 mixed and dispersed by a Banbury mixer is applied to the felt side of the paper support so that the coating amount is 25 g / m ^2. Coating was performed by a melt extruder (melting temperature: 320 ° C.) having a mold die. Further, the following polyolefin resin composition 2 was coated on the wire side of the paper support with the above melt extruder so that the coating amount was 20 g / m ² . Thereafter, the felt surface side is cooled and solidified with a mirror-like cooling roll, and the wire surface side is cooled and solidified. The smoothness (Oken type, J. TAPPI No. 5) is 6000 seconds, and the opacity (JIS P8138). A 93% resin-coated resin-coated paper was obtained.

・ Polyolefin resin composition 1
Linear low density polyethylene (density 0.926 g / cm ³ , melt index 20 g / 10 min) 35 parts, low density polyethylene (density 0.919 g / cm ³ , melt index 2 g / 10 min) 50 parts, anatase type dioxide Titanium (trade name: A-220, manufactured by Ishihara Sangyo Co., Ltd.) 15 parts, zinc stearate 0.1 part, antioxidant (trade name: Irganox 1010, manufactured by Ciba Specialty Chemicals) 0.03 parts, ultramarine (trade name) : Aoguchi Ultramarine NO.2000, manufactured by Daiichi Kasei Co., Ltd.) 0.09 part, and optical brightener (trade name: UVITEX OB, manufactured by Ciba Specialty Chemicals Co., Ltd.) 0.3 part are mixed to obtain polyolefin resin composition 1 Got.

・ Polyolefin resin composition 2
High density polyethylene (density 0.954 g / cm @ 3, a melt index 20 g / 10 min) 65 parts, low density polyethylene (density 0.919 g / cm ^3, melt index 2 g / 10 min) 35 parts by melt mixing the polyolefin resin Composition 2 was obtained.

[Manufacture of base materials]
A gelling agent was prepared by mixing and stirring 100 parts of a 6% aqueous solution of borax (gelling agent) and 3 parts of an aqueous 0.1% acetylene glycol surfactant solution (trade name: Olphine E1004, manufactured by Nissin Chemical Industry Co., Ltd.). A containing coating solution was prepared. Next, the gelling agent-containing coating solution was applied onto a smooth surface of the resin-coated paper with a Mayer bar and dried to form a gelling agent-containing layer. The coating amount of the gelling agent at this time was 1 g / m ² in terms of solid content.

(Preparation of gelling resin-containing coating solution)
5% polyvinyl alcohol (manufactured by Kuraray Co., Ltd., trade name: PVA-135H, polymerization degree: 3500, saponification degree: 99% or more) aqueous solution, 0.1% acetylene glycol surfactant (trade name: Olphine E1004, Nissin Chemical Industry Co., Ltd.) A very small amount of aqueous solution was mixed in water to prepare a gelling resin-containing coating solution having a coating solution concentration of 2.8%. The viscosity of this gelling resin-containing coating solution measured at 20 ° C. with a B-type viscometer was 95 mPa · s.

(Preparation of coating liquid A for forming an ink receiving layer)
[Preparation of cationic polymer-silica composite particle dispersion]
Gas phase method silica having an average particle size of 1.0 μm (manufactured by Nippon Aerosil Co., Ltd., trade name: Aerosil A300, average primary particle size: about 8 nm) is dispersed by a homomixer, and then the average secondary particle size reaches 800 nm. The mixture was pulverized and dispersed with a high-speed collision type homogenizer to prepare a 10% by mass silica fine particle dispersion.
10 parts by mass of a cationic compound having a 5-membered ring amidine structure (trade name: SC-700M, molecular weight: 30,000) having a 5-membered ring amidine structure is added to 100 parts by mass of this silica fine particle dispersion, and a high-speed flow collision type homogenizer is added. Was further dispersed to prepare a 10% cationic polymer-silica composite particle dispersion having an average secondary particle diameter of 0.15 μm.

  Cationic polymer-silica composite particle dispersion 100 parts (solid content) and 5% polyvinyl alcohol (manufactured by Kuraray Co., Ltd., trade name: PVA-135H, polymerization degree: 3500, saponification degree: 99% or more) aqueous solution 20 Part and an aqueous solution of 0.1% acetylene glycol surfactant (trade name: Orphin E1004, manufactured by Nissin Chemical Industry Co., Ltd.) in an aqueous solution are mixed to form an ink-receiving layer-forming coating having a solid content concentration of 10%. Liquid A was obtained. The viscosity of this coating liquid A for forming an ink receiving layer measured by a B-type viscometer at 20 ° C. was 90 mPa · s.

(Preparation of ink receiving layer forming coating solution B)
Cationic polymer-silica composite particle dispersion 100 parts (solid content) and 5% polyvinyl alcohol (manufactured by Kuraray Co., Ltd., trade name: PVA-135H, polymerization degree: 3500, saponification degree: 99% or more) aqueous solution 18 Part and an aqueous solution of 0.1% acetylene glycol surfactant (trade name: Orphin E1004, manufactured by Nissin Chemical Industry Co., Ltd.) in an aqueous solution are mixed to form an ink-receiving layer-forming coating having a solid content concentration of 10%. Liquid B was obtained. The viscosity of this coating liquid B for forming an ink receiving layer measured by a B-type viscometer at 20 ° C. was 80 mPa · s.

Experimental example 1
The gelling resin-containing coating liquid, the ink-receiving layer-forming coating liquid A, and the ink-receiving layer-forming coating liquid B are simultaneously applied to the surface of the base material containing the gelling agent with a slide bead test coater (manufactured by Trolla). After multilayer coating, it was dried with a hot air dryer to obtain an ink jet recording sheet. At that time, the gelling resin-containing coating liquid has a dry coating amount of 1.0 g / m ² , and the ink-receiving layer-forming coating liquid A has a dry coating amount of 10 g / m ^2. The ink receiving layer forming coating solution B was applied so that the dry coating amount was 10 g / m ² .

Experimental example 2
An ink jet recording sheet was obtained in the same manner as in Experimental Example 1 except that the gelling resin-containing coating liquid was applied in Experimental Example 1 so that the dry coating amount was 0.5 g / m ² .

Experimental example 3
An ink jet recording sheet was obtained in the same manner as in Experimental Example 1 except that the gelling resin-containing coating liquid was applied so that the dry coating amount was 2.0 g / m ² .

Experimental Example 4
An ink jet recording sheet was obtained in the same manner as in Experimental Example 1 except that the gelling resin-containing coating liquid was applied in Experimental Example 1 so that the dry coating amount was 3.0 g / m ² .

Experimental Example 5
In Experimental Example 1, an ink jet recording sheet was obtained in the same manner as in Experimental Example 1 except that the gelling resin-containing coating liquid was not applied.

Experimental Example 6
In Experimental Example 1, the ink receiving layer forming coating liquid A was applied so that the dry coating amount was 12 g / m ² , and the ink receiving layer forming coating liquid B was adjusted to 12 g / m ² . An ink jet recording sheet was obtained in the same manner as in Experimental Example 1 except that coating was performed.

Experimental Example 7
In Example 6, an inkjet recording sheet was obtained in the same manner as in Example 6 except that the gelling resin-containing coating solution was applied so that the dry coating amount was 0.5 g / m ² .

Experimental Example 8
In Example 6, an inkjet recording sheet was obtained in the same manner as in Example 6 except that the gelling resin-containing coating solution was applied so that the dry coating amount was 2.0 g / m ² .

  Each obtained ink jet recording sheet was visually observed to evaluate the surface state of the ink receiving layer. The evaluation results are shown in Table 1.

In Experimental Example 2 in which the dry coating amount of the gelling resin-containing coating liquid is small, the penetration amount of the gelling agent from the gelling agent-containing layer of the base material into the ink-receiving layer forming coating liquid is increased. A slight crack was observed on the surface of the receiving layer.
In Experimental Example 4 and Experimental Example 8 in which the dry coating amount of the gelling resin-containing coating liquid is large, the penetration amount of the gelling agent from the gelling agent-containing layer of the base material into the ink-receiving layer forming coating liquid is small. Therefore, a slight crack was observed on the surface of the ink receiving layer.
In Experimental Example 5 where the gelling resin-containing coating liquid was not applied, the amount of gelling agent penetrating from the gelling agent-containing layer of the base material into the ink-receiving layer forming coating liquid increased. Lateral cracks were observed on the surface of the layer.
For Experimental Examples 1, 3, 6, and 7, the dry coating amount of the ink-receiving layer-forming coating liquid was equal to or greater than that of Experimental Example 5, but the dry coating amount of the gelling resin-containing coating liquid was appropriate. By setting the thickness within the range, an ink receiving layer having no surface defects could be obtained.
Based on these results, the amount of gelling agent that permeates the coating solution for forming the ink receiving layer by adjusting the dry coating amount of the gelling resin-containing coating solution (dry coating amount of the gelling resin). It was found that can be adjusted.

It is a figure explaining one Embodiment of the manufacturing method of the sheet | seat for inkjet recording of this invention. It is sectional drawing which shows the sheet | seat for inkjet recording manufactured by one Embodiment of the manufacturing method of the sheet | seat for inkjet recording of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Slide bead coater 10 Backup roll 11 Base material 12 Gelling resin containing coating liquid 13 Coating liquid for ink receiving layer formation (A liquid)
14 Ink-receiving layer forming coating liquid (liquid B)
20 Slide head 21 Slide surface 22a, 22b, 22c Supply flow path 23a, 23b, 23c Manifold 24a, 24b, 24c Slot 32 Gelling resin content layer 33 Ink receiving layer

Claims (7)

A base material on which a gelling agent-containing layer containing a gelling agent is formed on one side of a support, a gelling resin-containing coating solution containing a gelling resin that gels with the gelling agent, fine particles, and the above A method for producing an inkjet recording sheet with an ink-receiving layer-forming coating liquid containing a gelling resin that gels with a gelling agent,
By coating the gelling resin-containing coating liquid on the gelling agent-containing layer of the substrate, and coating the ink-receiving layer forming coating liquid on the coated gelling resin-containing coating liquid, A method for producing an ink jet recording sheet, comprising adjusting an amount of a gelling agent penetrating from a gelling agent-containing layer of a base material into a coating liquid for forming an ink receiving layer.   By adjusting the gelling resin concentration in the gelling resin-containing coating liquid and / or the wet coating amount of the gelling resin-containing coating liquid, the ink receiving layer is formed from the gelling agent-containing layer of the substrate. The manufacturing method of the sheet | seat for inkjet recording of Claim 1 which adjusts the quantity of the gelatinizer which osmose | permeates the coating liquid for printing.   The method for producing an ink jet recording sheet according to claim 1, wherein the gelling agent is a crosslinking agent.   The method for producing an inkjet recording sheet according to claim 3, wherein the crosslinking agent is a boron-containing compound.   The method for producing an inkjet recording sheet according to any one of claims 1 to 4, wherein the gelling resin-containing coating liquid and the ink-receiving layer-forming coating liquid are subjected to simultaneous multilayer coating.   The manufacturing method of the sheet | seat for inkjet recording in any one of Claims 1-4 which carries out simultaneous multilayer coating of the gelling resin containing coating liquid and the coating liquid for several ink receptive layer formation. A base material on which a gelling agent-containing layer containing a gelling agent is formed on one side of a support, and a gelling-adjusting coating solution and a coating layer containing a gelling resin that gels with the gelling agent A method for producing a coated sheet with a coating liquid,
By coating the gelling adjustment coating liquid on the gelling agent-containing layer of the base material, and applying the coating layer forming coating liquid on the coated gelling adjustment coating liquid, The manufacturing method of the coating sheet | seat characterized by adjusting the quantity of the gelatinizer which osmose | permeates the coating liquid for coating layer formation from the gelatinizer containing layer of this.

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