JP3988625B2 - Method for manufacturing inkjet recording medium - Google Patents

Description

【００８４】
【発明の効果】
以上のように、本発明によるインクジェット記録媒体は、インクジェットプリンターによって画像や文字などの情報を記録する場合に、美観が良好で滲みやビーディングの発生もなく、オフセット印刷やグラビア印刷のもつ色域再現範囲を十分に満たすことのでき印刷用紙に近い風合いを有し、更に印画後の色の経時変化の少ない印刷校正用のインクジェット用記録媒体を得ることができた。
【図面の簡単な説明】
【図１】本発明のインクジェット用記録媒体の一実施例を示す縦断面図。
【符号の説明】
１・・・インクジェット用記録媒体
２・・・インク受容層
３・・・表面層
４・・・中間層
５・・・支持体[0001]
BACKGROUND OF THE INVENTION
When recording information such as images and characters with an ink jet printer, the present invention has good aesthetics and less bleeding and beading (reservoir density unevenness due to poor ink absorption). The present invention relates to a method for producing an ink jet recording medium that is suitable for printing proofreading applications with a wide gamut reproduction range and little color change with time.
[0002]
[Prior art]
In recent years, various types of printers are widely used for computer output. Among them, the ink jet printer is excellent in quietness, cost, simplicity, and image quality, can reproduce a full-color image with high quality, has excellent performance not found in other methods, and can be expected to further spread. Particularly in recent years, with the control of ink droplets, the development of dark and light inks, and the improvement in performance of recording media, the technology has progressed until an image comparable to a silver salt photograph can be obtained.
[0003]
With the development of such technology, inkjet printers are often used for offset printing and gravure printing calibration. Print proofing with an ink jet printer makes it possible to implement a remote proofing system, thus enabling quick proofing.
[0004]
In the ink jet recording method, it is general to use a water-based ink in which a dye is dissolved as the ink, and as the recording medium, a recording medium having an ink receiving layer formed on a support.
[0005]
Here, as a general technical example of a recording medium, the ink is made to be finely divided into silica by a physical action by a recording medium in which porous silica is dispersed in polyvinyl alcohol and a cationic component is added as an ink receiving layer. A method of chemically fixing the dye by absorbing it into the pores and adding a cationic component, or a method of chemically fixing the dye with alumina while physically absorbing the ink using an alumina sol, or There are methods such as those described in Patent Documents 1 and 2 in which a cationic resin is used to chemically fix a dye by a cation portion while physically absorbing ink by swelling.
[0006]
[Patent Document 1]
JP 2001-096911 A
[0007]
[Patent Document 2]
JP 2000-309157 A
[0008]
However, many conventional recording media have been developed with the aim of improving image quality, gloss, dryness, and water resistance, targeting silver halide photography. Therefore, although many of these characteristics are satisfactory, the color gamut reproduction range cannot satisfy the color gamut reproduction range of offset printing or gravure printing, and is not practical for printing proofing.
[0009]
For example, in the case of an ink jet recording medium that absorbs ink by swelling, a transparent resin can be used to obtain a material close to the original hue of the dye, and the color gamut reproduction range is widened. Ink absorption speed is slow to absorb water, and high-speed inkjet printers in recent years have not been able to obtain high image quality.
[0010]
In addition, in the case of an ink jet recording medium in which an ink receiving layer comprising a porous layer is provided and the ink is absorbed into the pores by a physical action, the ink absorbability is excellent, but the dye is contained in the ink receiving layer. As a result, the original hue of the dye cannot be obtained and the color reproduction range becomes narrow. Therefore, many ink jet recording media that form fine pores with fine particles on the surface of the ink receiving layer and maintain the dye on the surface of the ink receiving layer are considered, but the color gamut is excellent in ink absorptivity and image quality. The reproduction range does not satisfy the color gamut reproduction range in offset printing or gravure printing, which is insufficient for calibration purposes.
[0011]
In addition, in the case of an ink jet recording medium in which ink is absorbed into pores by a physical action, in order to further develop and stabilize the dye, a dye component can be contained in the ink receiving layer by adding a cationic component. A method of chemically fixing is used. Further, additives such as an antioxidant, an ultraviolet absorber, and a pH adjuster are contained in the ink receiving layer for the purpose of preventing change of the dye including light resistance and gas resistance over time. However, when these additives are mixed with the coating liquid for forming the ink receiving layer, there are problems such as aggregation, gelation, thickening, separation, and sedimentation of the coating liquid due to solvent, pH, ionicity, compatibility, etc. It was easy to generate and it was very difficult to select an additive suitable for the coating liquid of the ink receiving layer.
[0012]
[Problems to be solved by the invention]
In other words, the conventional technology is suitable for obtaining a texture or print similar to a silver halide photograph, but the color gamut reproduction range is insufficient for the texture and color gamut reproduction range of offset printing and gravure printing. It was.
[0013]
In general, in offset printing or gravure printing, image information is recorded by placing ink on a dedicated printing paper based on the image information, and drying or curing. At that time, a part of the printing ink penetrates into the inside of the paper, but most of the ink stays on the surface of the paper. Therefore, most of the pigment which is the coloring component also stays on the surface. The original hue of is fully expressed.
[0014]
On the other hand, in ink jet printing, ink jet ink basically permeates the inside of a coating layer called an ink receiving layer, and therefore a dye as a color developing component also permeates inside the ink receiving layer and is fixed and colored. Therefore, color development is affected by the transparency and refractive index of the ink-receiving layer film, as well as other components other than the dye in the ink, that is, the residual solvent and residual additive, and the hue inherent in the dye is not sufficiently expressed. There are many cases.
[0015]
Therefore, when an inkjet printer is used for color calibration of offset printing or gravure printing, the color reproduction range of offset printing or gravure printing is excellent even if the conventional inkjet recording medium has excellent image quality and text bleeding. However, it was narrow and not practical enough.
[0016]
In addition, cationizing agents, antioxidants, UV absorbers, pH adjusting agents, etc. for improving the color reproduction range and color change after printing are added to the coating solution for forming the ink receiving layer. It was difficult to do so, and it was difficult to stabilize the color after printing.
[0017]
The present invention has been made in view of such problems of the conventional technology, that is, when recording information such as images and characters by an ink jet printer, the appearance is good and bleeding and beading are not caused. The present invention relates to a method for producing an ink jet recording medium that is free from occurrence, particularly suitable for printing proofreading with a wide color gamut reproduction range of a recording portion, and with little color change over time of the recording portion.
[0018]
[Means for Solving the Problems]
  The present invention has been made to achieve the above object, and the invention described in claim 1 is an ink jet recording medium in which a porous ink receiving layer is provided on one side of a paper support. ,
  A solution containing at least one additive selected from a pH adjuster, a cationizing agent, an antioxidant, and an ultraviolet absorber is applied from the opposite side of the support to the ink receiving layer.And the additive penetrates to the surface of the ink receiving layer,
The additive is soluble in a solvent, or has fluidity at room temperature or below 100 ° C.It is a manufacturing method of the recording medium for inkjets obtained by this.
[0019]
By using paper as the support, a recording medium with a texture close to that of printing paper can be obtained, and by providing a porous ink-receiving layer on one side, the ink absorption effect can be increased, and the ink absorption capacity and absorption speed can be increased. Thus, an ink jet recording medium with less bleeding and beading corresponding to a high-speed, high-definition printer can be obtained. Furthermore, by applying a solution containing at least one or more additives selected from pH adjusters, cationizing agents, antioxidants and ultraviolet absorbers from the back side of the support, the color reproduction range is wide, An ink jet recording medium with little change over time can be obtained.
[0020]
As a method for providing a porous ink-receiving layer on a support, a method in which a coating solution obtained by mixing a dispersion or dispersion of a resin serving as a binder with a dispersion of fine particles is applied to a support and dried is generally used. Also known is a method of transferring a material coated on another support. It is also known to add a cationizing agent for fixing and fixing the color of the ink to the ink receiving layer.
[0021]
However, when adding a cationizing agent to the ink-receiving layer, if the cationizing agent is added to the ink-receiving layer coating liquid having a fine particle dispersion, the ink-receiving layer coating liquid is agglomerated or gelled, making it difficult to apply. Even when coating is possible, poor coating surfaces, thickening over time, settling, etc. often occur.
[0022]
Therefore, it is difficult to select a stable cationizing agent by adding an ink-receiving layer coating solution, and it is very difficult to select a cationizing agent effective for coloring and fixing of dyes.
[0023]
Similarly, additives such as pH adjusters, antioxidants, UV absorbers and the like are also prone to problems such as aggregation, gelation, thickening, and sedimentation when added to such ink-receptive layer coating liquids. In many cases, it is difficult to add to the ink receiving layer coating liquid even though it has an effect of acting on the dye inside.
[0024]
Therefore, after applying the ink-receiving layer coating liquid on the support and drying to form the ink-receiving layer, the ink-receiving layer is dissolved containing these cationizing agent, pH adjuster, antioxidant, ultraviolet absorber and other additives. There is a method of applying a liquid, but this may block pores on the surface of the porous ink-receiving layer, resulting in a decrease in ink absorbability. This is particularly remarkable when the surface of the ink receiving layer is made of fine particles and a water-soluble resin.
[0025]
Therefore, in the present invention, by applying a solution containing the additive from the back side of the support made of paper, the additive penetrates the paper base material, and further penetrates into the porous ink receiving layer to be contained in the ink receiving layer. An additive can be contained in the gap, and the void is retained in the ink receiving layer after drying.
[0026]
Making the surface layer of the ink receiving layer at least a layer made of dry silica and water-soluble resin or a layer made of anhydrous alumina, dry silica and water-soluble resin can be achieved by using fine, transparent dry silica having a relatively large specific surface area. By making the color development of the dye good and also using anhydrous alumina, which is also fine, transparent, and good in fixability of the dye, not only the color of the dye but also the color stability can be improved.
[0027]
Further, a strong and porous ink-receiving layer can be obtained by using a small amount of tough water-soluble resin as a binder for these fine particles. Furthermore, at least the ink receiving layer made of these materials has good color development and a wide color gamut reproduction range is achieved, and the surface of the ink receiving layer is smoothed and has an appropriate surface gloss close to that of printing proof paper. A recording medium can be obtained.
[0028]
In addition, by providing an intermediate layer composed of at least wet silica and silanol-modified polyvinyl alcohol between the surface layer of the ink receiving layer and the support, the porous layer weakly cross-linked with silanol groups has an appropriate absorption capability and has an intermediate capacity. It is considered that a solvent, an additive, and the like other than the dye in the ink are absorbed in the layer, and the dye molecule in the surface layer of the ink receiving layer tends to exist alone, thereby achieving a wide color gamut reproduction range.
[0029]
At the same time, a porous layer weakly crosslinked with a silanol group is applied to the support when a solution containing at least one additive selected from a pH adjuster, a cationizing agent, an antioxidant, and an ultraviolet absorber is applied from the back side. The ink containing the additive is penetrated to the surface of the ink receiving layer to form the ink receiving layer having the additive up to the surface of the ink receiving layer without blocking the penetration due to the dissolution and swelling by the solution penetrating from the back surface. Easy to do.
[0030]
Similarly, the use of non-coated paper for the support also forms an ink receiving layer having an additive in the vicinity of the ink receiving layer by penetrating the solution containing the additive applied from the back surface to the surface of the ink receiving layer. Becomes easy.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
The method for producing an inkjet recording medium of the present invention will be described in detail below.
[0032]
The method for producing an ink jet recording medium according to the present invention is a method for producing an ink jet recording medium having a wide color gamut reproduction range that is sufficiently practical for use in offset printing and gravure printing proofreading applications, and having little color change over time. is there.
[0033]
The ink receiving layer described in the present invention is a porous layer that can sufficiently absorb the ink ejected from the ink jet printer, and the support is an ink receiving layer formed on at least one side. It is a base material made of paper mainly composed of pulp and the like. The ink receiving layer is composed of one layer or two or more layers including a surface layer and an intermediate layer. The surface layer is a layer that can mainly accept ink ejected from the ink jet printer and fix the dye in the ink, and the intermediate layer is a layer that can mainly absorb the solvent, additive, etc. in the ink. .
[0034]
The porous ink image-receiving layer described in the present invention is preferably a layer having a large number of voids composed of at least a filler composed of fine particles and a binder resin serving as a binder. The filler is a commonly used filler, and examples thereof include silica, alumina, kaolin, clay, calcium carbonate, titanium oxide, zinc oxide, magnesium oxide, magnesium hydroxide, and aluminum hydroxide. Among them, the dry silica described in the present invention is also called a vapor-phase process silica, and is generally a silica produced by burning silicon tetrachloride with hydrogen and oxygen, and is characterized by extremely fine particles. Can be given.
[0035]
In particular, the dry silica used in the present invention uses an average particle size of 0.5 μm or less, which provides better surface smoothness and transparency of the surface layer, in order to improve the surface gloss and ink colorability of the ink receiving layer. preferable. The average particle size of dry silica here is the secondary particle size. Generally, dry silica cannot be present as finer primary particles, but is present as secondary particles that are aggregates. A diameter in the range of 0.1 μm to 0.5 μm can be used.
[0036]
Anhydrous alumina is also fine like dry silica, has good surface smoothness and transparency, and has a cationic surface, so that it can be used as a filler in the surface layer because it improves the coloring and stabilization of the dye.
[0037]
However, anhydrous alumina improves the stabilization of the dye, but the specific surface area is smaller than that of dry silica, and the ink absorbability is inferior. Therefore, it is desirable to use in combination with dry silica. In addition, wet silica produced by a gel method or a precipitation method is preferably used in the ink receiving layer because of its high oil absorption and excellent ink absorbability.
[0038]
A single ink-receiving layer using wet silica has too good ink absorbability, so that the dye of the ink penetrates into the inside and the color development of the dye becomes worse. It is preferable to use it as an intermediate layer. Further, by using wet silica having an average particle diameter of 2 to 5 μm, an intermediate layer excellent in smoothness and ink absorbability of the ink receiving layer can be obtained. In this case, if the average particle size is smaller than 2 μm, a sufficient gap cannot be formed in the intermediate layer to absorb the ink. If the average particle size is larger than 5 μm, the smoothness of the ink receiving layer is not good and the matte tone is used. Dot of ink is disturbed and the image quality deteriorates.
[0039]
Any binder resin can be used as a binder used in the porous ink image-receiving layer of the present invention. Generally, a polyvinyl alcohol, a urethane resin, an acrylic resin, and an ester resin are dissolved in a solvent. Or self-emulsified or emulsified with an emulsifier. At that time, it is important to select a binder that does not cause the filler to aggregate.
[0040]
Further, when a fine filler such as dry silica or anhydrous alumina is used, it is preferable to use a water-soluble resin rather than an emulsion because it can be firmly bound in a small amount, so that a porous ink image-receiving layer is provided.
[0041]
In addition, when polyvinyl alcohols are used, not only can an inkjet recording medium with high image quality and a wide color gamut reproduction range be manufactured at low cost, but also ink with excellent dispersion stability of dry silica and anhydrous alumina and excellent coating stability. A coating solution for the receiving layer can be obtained. In addition, if a silanol-modified polyvinyl alcohol is used in the intermediate layer, the porous layer weakly crosslinked by the silanol group becomes an appropriate absorption capacity, and the intermediate layer absorbs solvents and additives other than the dye in the ink, It is considered that a dye molecule in the surface layer of the ink receiving layer tends to exist alone and a wide color gamut reproduction range is achieved. The silanol-modified polyvinyl alcohols referred to in the present invention are polyvinyl alcohols having a silanol group, and the degree of saponification and the degree of polymerization are not particularly specified, but in order to increase the strength of the film, the degree of polymerization is 1000 or more. Use a good one.
[0042]
Known additives are used as the cationizing agent, pH adjusting agent, antioxidant, and ultraviolet absorber used in the present invention. Although not particularly limited, since it is permeated into the support and the porous ink-receiving layer, it is soluble in a solvent rather than a dispersion, or has a fluidity at room temperature or at 100 ° C. or lower. Preferably used.
[0043]
In addition, the support made of paper that can be used in the present invention may be paper mainly composed of pulp, such as chemical pulp such as LBKP, LBSP, LDP, NBKP, NBSP, NDP, GP, PGW, RMP, TMP, CTMP, CMP, CGP and other mechanical pulp, DIP and other waste paper pulp, etc., plain paper such as high-quality paper and medium-quality paper, and art paper, coated paper, and lightweight coated paper with a coating layer on it Fine coated paper can be used. In particular, by using plain paper such as ordinary high-quality paper and medium-quality paper, which is uncoated paper whose surface is not coated, the surface of the paper support opposite to the ink receiving layer is used. In the case where a solution containing at least one additive selected from pH adjusters, cationizing agents, antioxidants, and UV absorbers is applied, the solution penetrates into the support, and also on the ink receiving layer side. Easy to penetrate.
[0044]
Among them, the permeability of the additive solution is more effective from the support to the ink receiving layer, and the solvent and additive in the ink jet ink are effectively penetrated from the ink receiving layer to the support. 300 seconds or less / 100 CC is preferably used. When ink is printed on the ink receiving layer, if the air permeability is greater than 300 seconds, the gas in the void in the ink receiving layer is difficult to move to the paper side as the support, and it is difficult to replace the ink. Ink cannot penetrate quickly in the depth direction.
[0045]
For this reason, not only image bleeding and beading are likely to occur, but also non-volatile solvents and additives are not separated from the ink in the dye fixing layer, and the remaining color gamut is narrowed in the dye fixing layer. . In addition, the additive solution applied from the back surface of the support is also less likely to move from the back side of the support to the surface layer side of the ink receiving layer, as long as the air permeability is greater than 300 seconds. Additives such as cationizing agents, antioxidants, and UV absorbers remain in the ink receiving layer or in the support. Even if the ink is printed on the ink receiving layer, they come into contact with the dye, or contact with light or gas. It cannot be performed and the effect cannot be exhibited.
[0046]
The mixing ratio of the filler and the binder in the ink receiving layer is set so that the ink receiving layer has a void so as to be porous and the layer is firmly present as a layer with various fillers and binders. It is necessary. For example, in the surface layer of the ink receiving layer of the present invention, the mixing ratio of the dry silica and the water-soluble resin is preferably 40 to 120 parts by weight of the dry silica of the dye fixing layer with respect to 10 parts by weight of the water-soluble resin.
[0047]
When the ratio of silica increases, the strength of the coating film decreases and problems such as powder falling occur, and cracks on the film surface are conspicuous and the aesthetic appearance is impaired. Further, when the ratio of the water-soluble resin as the binder is increased, the absorbability is decreased, the occurrence of bleeding is increased, and further the color gamut reproduction range is narrowed.
[0048]
The mixing ratio of dry silica, anhydrous alumina and water-soluble resin is preferably 35 to 115 parts by weight of dry silica and 5 to 60 parts by weight of anhydrous alumina with respect to 10 parts by weight of water-soluble resin. When the ratio of dry silica and anhydrous alumina increases, the strength of the coating film similarly decreases, causing problems such as powder falling, and cracks on the film surface are conspicuous and the aesthetic appearance is impaired. Further, when the ratio of the water-soluble resin as the binder is increased, the absorbability is decreased, the occurrence of bleeding is increased, and further the color gamut reproduction range is narrowed.
[0049]
When the ratio of anhydrous alumina to dry silica increases, the dye fixing property improves, the color stability after printing increases, and the gloss of the surface increases, but the color reproduction range is narrowed. There is a need to.
[0050]
The mixing ratio of silanol-modified polyvinyl alcohol and wet silica in the intermediate layer is preferably 20 to 50 parts by weight of wet silica with respect to 10 parts by weight of silanol-modified polyvinyl alcohol. When the proportion of polyvinyl alcohol is increased, voids are not formed and the ink absorbability is deteriorated. As a result, the drying property of the ink image-receiving layer is deteriorated, and when the proportion of the filler is increased, the strength of the coating film is decreased. As a result, the surface strength of the ink receiving layer decreases.
[0051]
The coating amount of the ink receiving layer is usually 10 to 50 g / m²Degree. When the surface layer is provided, the coating amount of the surface layer is usually 3 g to 20 g / m.²Degree, preferably 5 to 15 g / m²Degree. If the thickness is too thin, the dye fixing ability will be insufficient, bleeding may occur or the color gamut reproduction range will be narrow, and conversely if the thickness is too thick, the cost will be high and curling, cracking, and powder falling will occur. Therefore, it is not preferable. Moreover, the coating amount of the intermediate layer is usually 5 to 40 g / m.²Degree, preferably 15-30 g / m²Degree.
[0052]
If the thickness is too thin, ink absorbability is lowered, and bleeding is generated on the surface of the ink receiving layer, drying property is delayed, and cockling is generated, which is not preferable. On the other hand, when the thickness is too thick, the cost is increased, and curling, cracking, and powder fall off are not preferable.
[0053]
The support is usually 80 to 200 g / m for good transportability to the ink jet printer.²It is preferable to use one having a degree.
[0054]
In the present invention, the ink-receiving layer may have a cross-linking agent, a fluorescent whitening agent, a surface-active agent for the purpose of improving the strength of the ink-receiving layer, adjusting the background color, or improving the stability of the ink-receiving layer coating liquid as necessary. Additives such as agents, antifoaming agents, preservatives, dispersants, colorants and the like may be arbitrarily selected from conventionally known additives within a range that does not prevent the object of the present invention.
[0055]
The ink receiving layer is provided on one side of the support. After applying a solution containing at least one additive selected from a pH adjuster, a cationizing agent, an antioxidant, and an ultraviolet absorber from the back side, A back layer can be provided on the opposite surface of the ink receiving layer as necessary for the purpose of preventing or improving the transportability to the printer.
[0056]
In the method for producing an ink jet recording medium of the present invention, a binder resin as a binder, a filler, and an additive are prepared by a conventionally known method of dispersing, mixing, or dissolving using a mixer, a disperser, or the like. The coating is applied to the surface of the support by a known coating method such as a roll coater method, a flade coater method, an air knife coater method, a gate roll coater method, a size press coater method, etc., and then using a hot air drying furnace, a thermal drum, etc. And drying to provide an ink receiving layer on the support.
[0057]
Thereafter, similarly, at least one or more selected from pH adjusters, cationizing agents, antioxidants, and UV absorbers prepared by a conventionally known method of dispersing, mixing, or dissolving using a mixer, a disperser, etc. From the surface of the support opposite to the ink-receiving layer, a known coating method such as a roll coater method, a flade coater method, an air knife coater method, a gate roll coater method is also used. Then, it is applied to the surface of the support by a size press coater method or the like, and then dried using a hot air drying furnace, a hot drum or the like to obtain the ink jet recording medium of the present invention.
[0058]
The timing of applying the solution containing the additive may be after the ink receiving layer is formed on the support, not only in the step of coating alone, but also after the ink receiving layer is applied. At the time of watering treatment for curling or adjusting the amount of water or at the time of coating the back layer, it may be used by mixing with a watering treatment solution or a back layer coating solution.
[0059]
<Action>
As described above, according to the method for manufacturing an ink jet recording medium of the present invention, when recording information such as images and characters with an ink jet printer, the appearance is good, and there is no occurrence of bleeding or beading. It is possible to obtain an ink jet recording medium having a texture and having a wide color gamut reproduction range particularly suitable for printing proofing and having little color change with time after printing.
[0060]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.
[0061]
<Support>
The paper used for the support was as shown below.
[0062]
・ Support A
High-quality paper: OK Prince fine quality 127.9 g / m²  (Oji Paper Co., Ltd.)
・ Support B
Coated paper OK Top Coat N 127.9 g / m²  (Oji Paper Co., Ltd.)
・ Support C
White polyester film WR712 100μm (Mitsubishi Chemical Polyester Film)
[0063]
<Ink receiving layer>
The coating liquid used for the ink receiving layer was prepared with the composition shown below.
[0064]
Ink receiving layer A
Wet silica X-37B (manufactured by Tokuyama) 10 parts by weight (average particle size 3.7 μm)
4 parts by weight of polyvinyl alcohol PVA-117 (manufactured by Kuraray Co., Ltd.)
86 parts by weight of water
[0065]
・ Ink receiving layer B
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.)
4 parts by weight of cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.)
86 parts by weight of water
[0066]
Ink receiving layer C
Wet silica X-37B (manufactured by Tokuyama) 10 parts by weight (average particle size 3.7 μm)
4 parts by weight of cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.)
86 parts by weight of water
[0067]
Ink receiving layer D
Dry silica A (average particle size 0.2 μm) 16 parts by weight
Polyvinyl alcohol PVA-617 (manufactured by Kuraray Co., Ltd.) 2 parts by weight
82 parts by weight of water
[0068]
・ Ink receiving layer E
Dry silica A (average particle size 0.2 μm) 12 parts by weight
Anhydrous Alumina A 4 parts by weight
Polyvinyl alcohol PVA-617 (manufactured by Kuraray Co., Ltd.) 2 parts by weight
82 parts by weight of water
[0069]
・ Ink receiving layer F
Dry silica A (average particle size 0.2 μm) 16 parts by weight
Acrylic emulsion AE-866 (manufactured by JSR) 10 parts by weight (solid content 20%)
76 parts by weight of water
[0070]
<Additives>
・ Additive A
Polyamine cationizing agent (solid content 70%) 2 parts by weight Water 98 parts by weight
・ Additive B
5 parts by weight of thioether antioxidant
95 parts by weight of water
・ Additive C
2 parts by weight of benzophenone UV absorber
98 parts by weight of water
・ Additive D
pH adjuster Sodium tetraborate solution (pH 9.18)
[0071]
<Production Methods of Examples and Comparative Examples>
Ink-receiving layers A to C on support A to C are applied in a dry coating amount of 20.0 g / m.²It apply | coated using a wire bar so that it might become, It was made to dry at 100 degreeC for 5 minute (s). Thereafter, the ink receiving layers D to F were applied at a dry coating amount of 10 g / m.²It apply | coated using a wire bar so that it might become, It was made to dry at 100 degreeC for 3 minute (s). Thereafter, additives A to D were applied from the back surface of the support with wire bar # 20 and dried at 100 ° C. for 5 minutes to obtain ink jet recording media of Examples 1 to 10 and Comparative Examples 1 and 2.
[0072]
Similarly, a dry coating amount of the ink receiving layer C on the support A is 20.0 g / m.²Then, using a wire bar, the coating is dried at 100 ° C. for 5 minutes, and then the ink receiving layer D is dried at a coating amount of 10 g / m.²It applied using a wire bar so that it might become, and was dried at 100 ° C for 3 minutes. Thereafter, the additive A was applied by wire bar # 20 from the surface layer side of the ink image-receiving layer of the support and dried at 100 ° C. for 5 minutes to obtain an ink jet recording medium of Comparative Example 3.
[0073]
Further, as a comparative example, the additive A was directly added to the coating liquid of the ink receiving layer C and the ink receiving layer D, mixed and stirred, and Comparative Examples 4 to 5 were obtained.
[0074]
An evaluation image is formed on the obtained inkjet recording medium using a Canon inkjet printer (product name BJ-F8500, ink cartridge BCI-8Y, 8M, 8C, 8PM, 8PC, 8PBK) to reproduce the color gamut. The range and surface gloss were checked and image quality, bleeding and cockling were evaluated.
[0075]
Further, the obtained printed matter was left in the room for one week, and the color change with time was confirmed.
[0076]
To confirm the color gamut reproduction range and the color difference over time, a colorimeter and Spectrolino manufactured by Gretag Macbeth were used, and for glossiness confirmation, the glossiness of the ink receiving layer surface was measured using a 60 ° glossmeter. . The criteria for evaluation are as follows.
[0077]
(image quality)
Photographic images of people, backgrounds, etc. were printed and evaluated visually.
○: A beautiful image can be obtained without beading or ink overflow.
Δ: Some beading or ink overflow is observed.
X: There are many overflows of beading and ink, and it is insufficient practically.
[0078]
(Bleed)
Several types of character patterns were printed and evaluated visually.
◯: There is no bleeding in the letters with letters or background, and they are sharp.
Δ: Characters are recognizable, although there are some blurs in the characters that are removed or in the background.
X: Bleeding is observed in a single character, which is insufficient for practical use.
[0079]
(Color gamut reproduction range)
The chart for color gamut confirmation was printed, the hue was measured, and it was confirmed whether the color gamut reproduction range possessed by offset printing or gravure printing could be covered.
A: The color gamut is sufficiently wide and sufficiently satisfies the color gamut reproduction range of printing.
B: The color gamut reproduction range of printing can be satisfied.
C: The color gamut is narrow and the color gamut reproduction range of printing cannot be satisfied.
[0080]
(Glossiness)
A: Glossiness is greater than 10% and has a glossiness equivalent to that of coated paper for printing.
B: The glossiness is 5 to 10%, and the gloss is close to that of coated paper for printing.
C: Glossiness is less than 5%, and glossiness equivalent to mat-coated paper is provided.
[0081]
(Color change with time)
A color gamut chart was printed, and the hues of Y, M, C, R, G, B, and K were measured, and the color difference ΔE after 30 minutes after printing and after standing for 1 week was confirmed.
A: ΔE ≦ 2, color change cannot be visually confirmed.
B: 2 <ΔE <5, a difference can be confirmed by visual alignment.
C: ΔE ≧ 5, a difference can be clearly confirmed visually.
[0082]
Table 1 shows the configurations of the fabricated examples and comparative examples and the evaluation results.
[0083]
[Table 1]

[0084]
【The invention's effect】
As described above, the ink jet recording medium according to the present invention has a good aesthetic appearance, no bleeding or beading, and has a color gamut of offset printing or gravure printing when recording information such as images and characters by an ink jet printer. It was possible to obtain an inkjet recording medium for print proofing that can sufficiently satisfy the reproduction range and has a texture close to that of printing paper and that has little color change with time after printing.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of an ink jet recording medium of the present invention.
[Explanation of symbols]
1 ... Inkjet recording medium
2 ... Ink receiving layer
3 ... Surface layer
4 ... Intermediate layer
5 ... Support

Claims (5)

In an inkjet recording medium in which a porous ink receiving layer is provided on one side of a support made of paper,
A solution containing at least one additive selected from a pH adjuster, a cationizing agent, an antioxidant, and an ultraviolet absorber is applied from the opposite side of the support to the ink receiving layer , and the additive is added. Penetrates to the surface of the ink receiving layer,
A method for producing an ink jet recording medium, wherein the additive is soluble in a solvent, or has fluidity at room temperature or 100C or less .   2. The method for producing an ink jet recording medium according to claim 1, wherein the surface layer of the ink receiving layer comprises at least dry silica and a water-soluble resin.   2. The method for producing an ink jet recording medium according to claim 1, wherein the surface layer of the ink receiving layer comprises at least dry silica, anhydrous alumina, and a water-soluble resin.   The inkjet recording according to any one of claims 1 to 3, wherein an intermediate layer comprising at least wet silica and silanol-modified polyvinyl alcohols is provided between the surface layer of the ink receiving layer and the support. A method for manufacturing a medium.   5. The method for producing an ink jet recording medium according to claim 1, wherein the support is non-coated paper.

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