JP4148056B2 - Inkjet recording medium - Google Patents

Description

  The present invention has good aesthetics when recording information such as images and characters with an ink jet printer, does not cause bleeding or cockling, has a particularly wide color gamut reproduction range, and is suitable for printing proofing applications. In addition, the present invention relates to an inkjet recording medium excellent in image storability.

  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 in 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 advanced until an image comparable to a silver salt photograph can be obtained.

  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.

  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.

  Here, as a general technical example of a recording medium, a recording medium provided with an ink-receiving layer in which porous silica is dispersed in polyvinyl alcohol and a cationic component is added, the ink is silica by a physical action. The dye is chemically fixed by absorbing it into the pores and adding a cationic component, or the dye is chemically fixed by alumina while physically absorbing the ink using alumina sol. There is a method, or a method of using a cationic resin and chemically fixing a dye by a cation part while physically absorbing ink by swelling.

  However, many of such general recording media have been developed for the purpose of improving image quality, gloss, dryness, and water resistance with silver salt photography as a target. Therefore, many of these characteristics are satisfactory, but 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.

  For example, in the case of an ink jet recording medium in which ink is absorbed into pores by a physical action, although the ink absorbs excellently, the dye develops color inside the receiving layer, so that the inherent dye has Hue cannot be obtained, and the color reproduction range becomes narrow.

  Inkjet recording media with fine pores are excellent in ink absorptivity and image quality, but the color gamut reproduction range does not satisfy the color gamut reproduction range in offset printing and gravure printing, and calibration It was insufficient as a use.

  In addition, in the ink jet recording medium in which pores are formed with such fine particles, there is a problem that the dye that has been absorbed is easy to touch the air and the hue of the dye changes with time.

  In addition, in the case of an ink jet recording medium that absorbs ink by swelling, by using a transparent resin, a material close to the original hue of the dye can be obtained, the color gamut reproduction range is widened, and the absorbed ink Is difficult to touch the air, so that the change of the dye with time is small, but the ink absorption speed is slow to absorb the ink while swelling, and high-speed inkjet printers in recent years have not been able to obtain high image quality.

  In other words, the conventional technique is suitable for obtaining a texture or print similar to a silver halide photograph, but the color gamut reproduction range is insufficient with respect to the color gamut reproduction range possessed by offset printing or gravure printing. .

  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 a coloring component also stays on the surface. The original hue of is fully expressed.

  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.

  Therefore, when an inkjet printer is used for color calibration for offset printing or gravure printing, the color reproduction range of offset printing or gravure printing is excellent even when the conventional inkjet recording medium has excellent image quality and text bleeding. However, it was narrow and not practical enough.

  The present invention has been made in view of such problems of the conventional technology, i.e., when recording information such as images and characters by an ink jet printer, it has good aesthetics and is free from bleeding and cockling. The present invention relates to an ink jet recording medium that is free from occurrence and particularly has a wide color gamut reproduction range of a recording portion, is excellent in image storability, and is suitable for printing proofreading applications.

The present invention has been made to achieve the above object, and the invention according to claim 1 of the present invention includes, as shown in FIG. 1, at least average particles on at least one side of a support 5 made of non-coated paper. An intermediate layer 4 made of silanol-modified polyvinyl alcohol containing a filler of 70 to 95% by weight of wet silica having a diameter of 2 to 5 μm and 30 to 5% by weight of calcium carbonate, and at least an average particle size of 0.4 μm or less An ink receiving layer is provided in which a dye fixing layer composed of cationic dry silica and a binder is laminated in this order . The intermediate layer 4 is filled with 10 parts by weight of silanol-modified polyvinyl alcohol. On the other hand, the inkjet recording medium 1 is 20 to 50 parts by weight .

The invention according to claim 2 of the present invention, an inkjet recording medium 1 according to the first aspect, the cationic dry silica of the dye fixation layer 3, with respect to the binder 10 parts by weight, 40 to 120 weight An ink jet recording medium.

  The ink jet recording medium according to the present invention has a good aesthetic appearance, no bleeding and cockling, and has a sufficient color gamut reproduction range for offset printing and gravure printing when recording information such as images and characters with an ink jet printer. Therefore, it is possible to obtain an ink jet recording medium for printing calibration having a texture close to that of printing paper and having excellent image storage stability.

  According to the ink jet recording medium 1 of the present invention, when characters and image information are recorded by an ink jet printer, the obtained image quality is excellent, and cockling and undulation of the recording portion as the ink receiving layer 2 is also achieved. In particular, it has a wide color gamut reproduction range, can be used for printing and proofing of offset printing and gravure printing, has a sufficiently practical wide color gamut reproduction range, and has excellent image storage stability. An ink jet recording medium can be obtained.

  This is because, by using cation-modified dry silica having an average particle size of 0.4 μm or less and a binder in the dye fixing layer 3, the dye fixing property is improved by the cation component. This is because many dyes are fixed on the upper part of the dyeing layer.

  Further, by setting the average particle size of the dye fixing layer 3 to 0.4 μm or less, the wavelength of the visible region of the light is reduced, so that the transparency of the dye fixing layer 3 is increased, and the color developability is further improved. A recording medium 1 having an appropriate surface gloss close to that of a printing proof sheet can be obtained by achieving the reproduction range and smoothing the surface of the receiving layer 2.

  Moreover, among the fillers of the intermediate layer 4, dry silica has a relatively large specific surface area, so that the color developability is good. Further, by using a silanol-modified polyvinyl alcohol and a filler as the intermediate layer 4, the porous layer weakly cross-linked by the silanol group has an appropriate absorption capacity, and the intermediate layer 4 has a solvent other than the dye in the ink. It is considered that a wide color gamut reproduction range is achieved because the dye molecules in the dye fixing layer are likely to be present singly and the additives are absorbed.

  Further, as the filler for the intermediate layer 4, wet silica and calcium carbonate having an average particle diameter of 2 to 5 μm are blended in an amount of 5 to 30% by weight of calcium carbonate with respect to 70 to 95% by weight of wet silica. While maintaining the smoothness of the medium 1, solvents and additives other than the dye in the ink are more effectively absorbed by the intermediate layer 4 to achieve wide color gamut reproduction, and the hue change of the absorbed dye. Can also be suppressed. This is achieved by blending wet silica, which has a relatively large surface area and is porous and excellent in water absorption, and calcium carbonate which is slightly inferior in water absorption but is alkaline and has an effect of suppressing deterioration of the dye. .

  Furthermore, by using non-coated paper as the support 5, the solvent, additives, etc. permeate into the inside of the recording medium more appropriately than the coated paper, and the dye molecules in the dye fixing layer 3 are likely to exist alone. As a result, there is no blurring and a wide color gamut reproduction range is achieved, and a higher quality image can be obtained.

In addition, the filler of the intermediate layer 4 is 20 to 50 parts by weight with respect to 10 parts by weight of the silanol-modified polyvinyl alcohol, so that the solvent or additive other than the dye in the ink can more effectively prevent the intermediate layer. Inkjet image-receiving paper that is absorbed into the ink 4 and has a wider color gamut reproduction range without blurring or the like can be obtained.

  Furthermore, in the ink-receiving layer 2, the dye-fixing layer 3 is 40 to 120 parts by weight with respect to 10 parts by weight of the binder in the dye-fixing layer 3 so that the dye-fixing layer 3 is removed from above the ink-receiving layer 2. Sufficient voids can be obtained to quickly absorb the ink into the dye fixing layer 3, and image defects such as bleeding and beading and drying defects can be reduced.

  As described above, according to the ink jet recording medium 1 of the present invention, when information such as images and characters is recorded by an ink jet printer, the appearance is good, there is no occurrence of bleeding or cockling, and it is close to printing paper. To obtain an inkjet recording medium 1 having a texture, in particular, having a wide color gamut reproduction range of the ink receiving layer 2 as a recording portion, suitable for printing proofing, having little dye hue change, and excellent image storability. Can do.

  The ink jet recording medium 1 of the present invention will be described in detail below. FIG. 1 is a side sectional view of the ink jet recording medium 1 of the present invention, and an average is formed on one side of a support 5 made of non-coated paper. An intermediate layer 4 made of silanol-modified polyvinyl alcohol containing a filler composed of 70 to 95% by weight of wet silica having a particle diameter of 2 to 5 μm and 30 to 5% by weight of calcium carbonate is laminated.

  On the intermediate layer 4, a dye fixing layer 3 composed of cationic dry silica having an average particle size of 0.4 μm or less and a binder is laminated to form an ink by the intermediate layer 4 and the dye fixing layer 3. The receiving layer 2 is provided.

  The ink receiving layer 2 described in the present invention is a layer that can sufficiently absorb ink ejected from an ink jet printer, and is composed of at least two layers of an intermediate layer 4 and a dye fixing layer 3.

  The dye fixing layer 3 is a layer that can mainly fix a dye in the ink, and the intermediate layer 4 is a layer that can mainly absorb a solvent, an additive, and the like in the ink. The support 5 is a base material on which the ink receiving layer 2 can be formed on at least one surface thereof.

  The silanol-modified polyvinyl alcohols described 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. It is better to use one.

  Furthermore, the filler in the intermediate layer 4 of the present invention is wet silica prepared by gel method or precipitation method and natural or synthetic calcium carbonate. When wet silica is used, it is preferable because it has a high oil absorption and excellent ink absorbency. Further, it is preferable to use wet silica having an average particle diameter of 2 to 5 μm, which is an intermediate between excellent smoothness and ink absorbability of the ink receiving layer 2. Layer 4 can be obtained.

  In this case, if the average particle size is smaller than 2 μm, it is not possible to create a sufficient space for absorbing the ink in the intermediate layer 4, and if it is larger than 5 μm, the smoothness of the ink receiving layer 2 is poor and the matte tone is obtained. Not only that, the dots of the printed ink are disturbed and the image quality deteriorates.

  In addition, calcium carbonate is generally obtained by a method in which carbon dioxide is blown into a suspension of heavy calcium carbonate and calcium hydroxide obtained by pulverizing and classifying natural limestone, etc., or a method in which sodium carbonate is reacted. Sedimentable (synthetic) calcium carbonate (or light calcium carbonate) is known, but any calcium carbonate can be used in the present invention.

Although any calcium carbonate has a smaller specific surface area than wet silica and inferior in ink absorbency, the surface is on the alkaline side, and compared to silica, oxidizing gas in the light and air, etc. (
Ozone, nitrogen dioxide, sulfur dioxide, etc.) are not significantly affected by the environment, and have the effect of suppressing dye discoloration.

  The calcium carbonate used in the intermediate layer 4 of the present invention preferably has an average particle diameter of 2 to 5 μm, like wet silica, from the viewpoint of smoothness and ink absorbability of the ink receiving layer 2.

  If calcium carbonate having an average particle diameter of 2 to 5 μm is further used in the surface dye fixing layer 3, it can be expected to be more effective in suppressing the discoloration of the dye, but the smoothness and ink absorbability of the surface of the ink receiving layer 2 can be further improved. Since it is damaged, it is difficult to use it for the dye fixing layer 3, and by using it for the lower intermediate layer 4, the effect of suppressing discoloration of the dye can be sufficiently obtained.

  The ratio of wet silica and calcium carbonate in the intermediate layer 4 is 5 to 30% by weight of calcium carbonate with respect to 70 to 95% by weight of wet silica. When the amount of calcium carbonate is less than this range, the effect of suppressing the hue change due to the deterioration of the dye is almost lost, and when the amount of calcium carbonate is large, the voids in the intermediate layer 4 are reduced and the dye in the ink absorbed in the ink receiving layer 2 is lost. Solvents, additives, and the like other than those are not absorbed into the intermediate layer 4 more effectively, and image defects such as image bleeding and beading tend to occur.

  The dry silica used for the filler of the dye fixing layer 3 described in the present invention is also called vapor phase silica, and is generally silica produced by burning silicon tetrachloride with hydrogen and oxygen. The particles are very fine.

  In particular, the dry silica used in the dye fixing layer 3 of the present invention makes the surface smoothness and transparency of the dye fixing layer 3 more satisfactory in order to improve the surface gloss and ink color development of the ink receiving layer 2. The average particle size is used. 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 thereof. A secondary particle size in the range of 0.1 μm to 0.4 μm can be used. Cationic silica is obtained by cationizing the surface of dry silica with a cationic compound. Normally, untreated dry silica has an anionic surface, but it is sufficiently cationized to completely cationize the surface. Make it sex.

  The cationic compound may be an organic compound or an inorganic compound. Further, not only a compound having an electrically positive charge, but also a compound having a functional group that exhibits a cationic property by electrolysis when dispersed in water.

  For example, surface treatment with an organic compound or polymer having a quaternary ammonium salt and cationizing the surface of dry silica, or surface treatment of dry silica with an organic compound or polymer having an amine, Treatment with alkyl halide or Lewis acid and cationization as amine salt, or surface treatment of dry silica with inorganic compound of alumina, titanium or magnesium or its oxide to cationize, amino group There is a method of cationizing the surface by subjecting dry silica to a surface treatment with an organic compound or polymer, and dispersing it in water to electrolyze amino groups. In the method of cationizing the surface by electrolysis, it is necessary that the pH of the colloidal dispersion of dry silica be sufficiently lower than the isoelectric point.

  The binder for the dye-fixing layer 3 of the present invention may be of any type, but is generally used by dissolving polyvinyl alcohol, urethane resin, acrylic resin, ester resin in a solvent, or self-emulsifying. Alternatively, it is used after being emulsified with an emulsifier. At that time, it is important to select a binder that does not cause the cationic dry silica to aggregate.

  In particular, when polyvinyl alcohols are used, not only can the inkjet recording medium 1 having high image quality and a wide color gamut reproduction range be produced at low cost, but also a dye having excellent dispersion stability of cationic dry silica and excellent coating stability. A coating solution for the fixing layer 3 can be obtained. Furthermore, in order to improve this stability, it is preferable to adjust the pH of the coating solution for the dye fixing layer 3 to 6.0 or less, and more preferably to 5.0 or less.

  The uncoated paper described as the support 5 in the present invention is a paper whose surface is not coated, and general high quality paper, medium quality paper, and the like are used. Among them, in order to effectively penetrate the solvent and additives in the ink from the dye fixing layer 3 constituting the ink receiving layer 2 into the intermediate layer 4, those having an air permeability of 300 seconds or less / 100 cc are preferable. Used. When ink is printed on the dye fixing layer 3, if the air permeability is longer than 300 seconds, the gas in the gaps in the intermediate layer 4 and the dye fixing layer 3 is difficult to move to the paper side as the support 5. In addition, it becomes difficult to replace the ink, and the ink cannot penetrate quickly in the depth direction. For this reason, not only image bleeding and beading are likely to occur, but also non-volatile solvents and additives remain in the dye fixing layer 3 without being separated from the ink in the dye fixing layer 3, thereby narrowing the color gamut. Will be.

  Further, the sizing degree and whiteness of the non-coated paper as the support 5 are not particularly limited. However, when the sizing agent is added internally and the sizing degree is approximately 15 seconds or more, the ink receiving layer 2 is used. This is preferable because the coating process is easier, but if the steecht sizing degree is too high, the absorbency is reduced, and bleeding and the color gamut reproduction range are reduced. Therefore, an appropriate one is selected in consideration of balance. .

  The mixing ratio of the silanol-modified polyvinyl alcohol and the filler in the intermediate layer 4 is preferably 20 to 50 parts by weight of the filler with respect to 10 parts by weight of the silanol-modified polyvinyl alcohol. When the proportion of the polyvinyl alcohol is increased, voids are not formed, the ink absorbability is deteriorated. As a result, the drying property of the ink receiving layer 2 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 2 is lowered.

  The mixing ratio of the cationic dry silica and the binder in the dye fixing layer 3 of the ink receiving layer 2 is preferably 40 to 120 parts by weight of the cationic dry silica and 10 parts by weight of the binder. When the proportion of the cationic dry 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 binder is increased, the absorbability is lowered, the occurrence of bleeding is increased, and further the color gamut reproduction range is narrowed.

The coating amount of the intermediate layer 4 is usually about 10 to 40 g / m ² , preferably about 15 to 30 g / m ² . If the thickness is too thin, the ink absorbability is lowered, bleeding occurs on the surface of the ink receiving layer 2, the drying property is slowed, and cockling occurs. On the other hand, when the thickness is too thick, the cost is increased, and curling, cracking, and powder fall off are not preferable.

The coating amount of the dye fixing layer 3 is usually about 3 g to 20 g / m ² , preferably about 5 g to 15 g / m ² . If the thickness is too thin, the dye fixing ability will be insufficient, bleeding will occur and 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. It is not preferable.

In general, the support 5 is preferably about 80 to 200 g / m ² for good transportability to an ink jet printer.

  In the present invention, the intermediate layer of the ink receiving layer 2 and the dye fixing layer 3 are optionally provided with an antioxidant, a cationizing agent, a cross-linking agent, a dye fixing agent, a fluorescent brightening agent, a surfactant, a quenching agent. Additives such as foaming agents, pH adjusting agents, preservatives, ultraviolet absorbers, and dispersants may be arbitrarily selected from conventionally known ones as long as the object of the present invention is not prevented.

  Further, the ink receiving layer 2 can be provided on one side or both sides of the support 5, but when provided on one side, the ink receiving layer 2 is opposite to the ink receiving layer 2 as necessary in order to prevent curling and improve transportability to the printer. A back layer can be provided on the surface.

  In preparing the inkjet recording medium 1 of the present invention, a conventionally known method of dispersing, mixing, or dissolving a resin, a filler, and an additive using a disperser or the like may be used.

  Also, the coating is applied to the surface of the support by a known 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 or the like. Then, it dries using a hot air drying furnace, a thermal drum, etc., and the inkjet recording medium 1 of this invention is obtained.

  Hereinafter, the ink jet recording medium of the present invention will be specifically described with reference to examples.

  The following support paper, intermediate layer ink, and dye fixing layer ink were used as materials for producing the inkjet recording medium of the present invention.

<Support paper>
A: Fine paper (manufactured by Gojo Paper Co., Ltd.) 127.9 g / m ²
(Air permeability 200sec / 100cc)
B: Coated paper OK Top Coat N (manufactured by Oji Paper Co., Ltd.) 127.9 g / m ²
(Air permeability 1000 seconds / 100cc)
<Interlayer ink>
A: Wet silica X-37B (manufactured by Tokuyama Corporation) (average particle size 3.7 μm) 9 parts by weight Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Flour & Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.) 4 parts by weight Water 86 parts by weight B: Wet silica X-37B (manufactured by Tokuyama Corporation) (average particle size 3.7 μm) 10 parts by weight Cyanol-modified polyvinyl alcohol R-1130 ( Kuraray Co., Ltd.) 4 parts by weight Water 86 parts by weight C: Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 10 parts by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray) 4 parts by weight Water 86 parts by weight D: Wet silica X-37B (manufactured by Tokuyama) 9.8 parts by weight (average particle size 3.7 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 0.2 parts by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.) 4 parts by weight Water 86 parts by weight E: Wet silica X-37B (manufactured by Tokuyama) 6 parts by weight (average particle size 3.7 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 4 parts by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray) 4 parts by weight Water 86 parts by weight F: wet silica X-37B (manufactured by Tokuyama) 9 parts by weight (average particle size 3.7 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Polyvinyl alcohol PVA-117 (manufactured by Kuraray) 4 parts by weight Water 86 parts by weight G: wet silica T-32 (manufactured by Tokuyama) 9 parts by weight (average particle size 1.6 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray) 4 parts by weight Water 86 parts by weight H: wet silica X-60 (manufactured by Tokuyama) 9 parts by weight (average particle size 6 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.) 4 parts by weight Water 86 parts by weight I: wet silica X-37B (manufactured by Tokuyama Corporation) 9 parts by weight (average particle size 3.7 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray) 6 parts by weight Water 84 parts by weight J: wet silica X-37B (manufactured by Tokuyama) 9 parts by weight (average particle diameter 3.7 μm)
Calcium carbonate μ-POWDER 3N (manufactured by Bihoku Powder Chemical Co., Ltd.) 1 part by weight (average particle size 3 μm)
Cyanol-modified polyvinyl alcohol R-1130 (manufactured by Kuraray Co., Ltd.) 1 part by weight Water 89 parts by weight <Dye fixing layer ink>
A: Cationic dry silica A (average particle size 0.2 μm) 16 parts by weight Polyvinyl alcohol PVA-617 (manufactured by Kuraray) 2 parts by weight Water 82 parts by weight B: Colloidal silica PS-MO (manufactured by Nissan Chemical Industries) 16 Parts by weight (average particle size 0.12 μm)
Polyvinyl alcohol PVA-617 (manufactured by Kuraray) 2 parts by weight Water 82 parts by weight C: Cationic dry silica B (average particle size 0.6 μm) 16 parts by weight Polyvinyl alcohol PVA-617 (manufactured by Kuraray) 2 parts by weight water 82 Part by weight D: Cationic dry silica A (average particle size 0.2 μm) 14 parts by weight Polyvinyl alcohol PVA-617 (manufactured by Kuraray) 4 parts by weight Water 82 parts by weight E: Cationic dry silica A (average particle size 0. 0) 2 μm) 15 parts by weight Polyvinyl alcohol PVA-617 (manufactured by Kuraray Co., Ltd.) 1 part by weight Water 84 parts by weight For each of the ink jet inks of the present invention and comparative examples according to Examples 1 to 5 and Comparative Examples 1 to 12 shown below. A recording medium 1 (see FIG. 1) was produced.

The intermediate layer ink A is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. An ink jet recording medium 1 of the invention was obtained.

The intermediate layer ink A is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink D was applied using a wire bar so that the dry coating amount was 10 g / m ² and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. An ink jet recording medium 1 of the invention was obtained.

<Reference Example 1>
The intermediate layer ink A is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink E was applied using a wire bar so that the dry coating amount was 10 g / m ² and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. An ink jet recording medium 1 of the invention was obtained.

<Reference Example 2>
The intermediate layer ink I is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. An ink jet recording medium 1 of the invention was obtained.

The intermediate layer ink J is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. An ink jet recording medium 1 of the invention was obtained.

<Comparative Example 1>
The intermediate layer ink A is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink B was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative example 2>
The intermediate layer ink A is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink C was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 3>
The intermediate layer ink B is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative example 4>
The intermediate layer ink C is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 5>
The intermediate layer ink D is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ² , dried at 100 ° C. for 3 minutes to form the dye fixing layer 3, and ink jet according to Comparative Example 5 A recording medium 1 was obtained.

<Comparative Example 6>
The intermediate layer ink E is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 7>
The intermediate layer ink F is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 8>
The intermediate layer ink G is applied onto the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 9>
The intermediate layer ink H is applied on the support 5 made of the support paper A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ² and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 10>
The intermediate layer ink A is applied onto the support 5 made of the support paper B using a wire bar so that the dry coating amount is 20.0 g / m ^2, and is dried at 100 ° C. for 5 minutes. Formed. Thereafter, the dye fixing layer ink A was applied using a wire bar so that the dry coating amount was 10 g / m ^2, and dried at 100 ° C. for 3 minutes to form the dye fixing layer 3. A recording medium 1 was obtained.

<Comparative Example 11>
The intermediate layer ink A is coated on the support 5 made of the support sheet A using a wire bar so that the dry coating amount is 20.0 g / m ^2, and dried at 100 ° C. for 5 minutes to form the intermediate layer 4. Formed. Thereafter, the dye fixing layer 3 was not formed, and an ink jet recording medium without the dye fixing layer 3 according to Comparative Example 11 was obtained.

<Comparative Example 12>
Without forming the intermediate layer 4 on the support 5 made of the support paper A, the dye fixing layer ink A was directly applied using a wire bar so that the dry coating amount was 10 g / m ^2, and the temperature was 100 ° C. The dye fixing layer 3 was formed by drying for 3 minutes to obtain an ink jet recording medium without the intermediate layer 4 according to Comparative Example 12.

  An evaluation image was formed on the ink receiving layer 2 of the ink jet recording medium 1 obtained in Example 1 above using a Canon ink jet printer (product name BJ-F870), and the color gamut reproduction range and hue were changed. The change over time and surface gloss were measured, and the image quality and bleeding were evaluated.

  Using a colorimeter (Spectrelino manufactured by Gretag Macbeth), measure the L * a * b value, check the color gamut reproduction range, and calculate the color difference ΔE from the change in the L * a * b value over time. The change in hue over time was confirmed. The glossiness was confirmed by measuring the glossiness of the surface of the ink receiving layer 2 using a 60 ° glossmeter. Image quality, bleeding, and cockling were visually evaluated. The criteria for evaluation are as follows.

(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.

(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 have been removed or the background.

  X: Bleeding is observed in a single character, which is insufficient for practical use.

(Glossiness)
A: Glossiness is greater than 10% and has 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.

(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.

(Hue change over time)
A color gamut chart was printed, and after 30 minutes from printing and after storing for 1 week at room temperature and humidity, hue measurement was performed, and a hue difference ΔE after 1 week with respect to the hue after 30 minutes from printing was calculated.

A: The maximum value of ΔE is ΔE <2 (the hue change is unknown even when compared with the naked eye)
B: The maximum value of ΔE is 2 ≦ ΔE ≦ 4 (a change in hue can be seen by comparison with the naked eye)
C: The maximum value of ΔE is 4 <ΔE (a clear hue change can be seen with the naked eye)
The results are shown in Table 1.

1 is a longitudinal sectional view showing an embodiment of an inkjet recording medium of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Recording medium for inkjet 2 ... Ink receiving layer 3 ... Dye fixing layer 4 ... Intermediate | middle layer 5 ... Support body

Claims (2)

It consists of silanol-modified polyvinyl alcohol containing a filler of 70 to 95% by weight of wet silica having an average particle diameter of 2 to 5 μm and 30 to 5% by weight of calcium carbonate on at least one side of a support made of uncoated paper. There is provided an ink receiving layer in which an intermediate layer and a dye fixing layer composed of cationic dry silica having an average particle size of 0.4 μm or less and a binder are laminated in this order, and the intermediate layer filler. An ink jet recording medium , wherein the content of the silanol-modified polyvinyl alcohol is 20 to 50 parts by weight with respect to 10 parts by weight . 2. The inkjet recording medium according to claim 1, wherein the cationic dry silica of the dye fixing layer is 40 to 120 parts by weight with respect to 10 parts by weight of the binder.