JP2002166646A - Material to be recorded by ink-jet recording and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive material to be recorded by ink jet recording having high printability and reducing discoloration and fading of printing. SOLUTION: In the material to be recorded by ink-jet recording obtained by forming an ink receiving layer comprising one layer or two or more layers on at least one surface of a base material, a fiber fine powder is added to at least one layer constituting the ink receiving layer as a main component or one component of a pigment. The content of the fiber fine powder is set to 20 wt.% or more, preferably, 50 wt.% or more with respect to the whole of the pigment in the fiber fine powder-containing layer. Further, a cationic substance, for example, an aluminum compound is added to the fiber fine powder-containing layer in addition to the fiber fine powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recording material for ink jet recording and a method for producing the same.

[0002]

2. Description of the Related Art Ink jet printers, which eject liquid ink in a jet form from nozzles having a special structure and control the trajectories of the ink to adhere to paper for printing, are widely used for printers such as facsimile machines, word processors, and personal computers. Have been. The paper used for this includes the fixing properties and absorbency of the inkjet ink, print density, roundness of dot shape, sharpness around dots, whiteness, water resistance, and dimensional stability due to moisture absorption and desorption. An ink jet recording material having the above characteristics is used.

In order to obtain printing quality characteristics among these characteristics, it is generally effective to provide a coating layer containing silica as a main component of the pigment. A coating layer is provided. Further, in order to increase whiteness, fluorescent dyes, whitening agents such as color dyes and pigments, color appearance adjusting agents and the like are used.

[0004] However, among the above-mentioned ink jet recording materials, particularly, recording materials on which photographs or graphic data are printed are used for applications such as decorating a wall or the like, or being used as a display, or exposed to light, or as an album or a collection of works. Often used for long-term storage. For this reason, there has been an increasing demand for an ink jet recording material having not only high print quality but also less discoloration of print. Further, the ink jet recording material is generally expensive, and there is an increasing demand for cost reduction.

[0005]

However, silica, which is the most widely used pigment for the surface coating of an ink jet recording material, has a very high surface activity and is effective in improving the printing quality. However, there is a disadvantage that the discoloration of the whitening agent and the color appearance adjusting agent such as the dye or the fluorescent dye, the color dye and the pigment in the paper is accelerated. Further, silica is generally expensive, which increases the cost of the ink jet recording material.

An object of the present invention is to eliminate such inconveniences and to provide a low-cost ink jet recording material having not only high printability but also less discoloration of print.

[0007]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the above object, and as a result, in an ink jet recording material having an ink receiving layer formed on at least one surface of a substrate, Fine powder of fibers (fiber fine powder) is used as the main component or one component of the pigment of at least one layer constituting the ink receiving layer, and the fine powder of the fiber is used as the main component or one component of the fiber. The layer is used at a predetermined ratio with respect to the entire pigment contained in the “fiber fine powder-containing layer” as appropriate, thereby providing not only high printability but also less discoloration of the print. It was found that a low-cost ink jet recording material could be obtained. In this case, it was also found that a more remarkable effect can be obtained by using the fiber fine powder and the cationic component together. Since the fiber fine powder is basically a fiber similar to the paper component, the ink absorbency is high,
Moreover, since the fiber length is short, feathering, which is a bleeding along the fiber generated by long cellulose fiber in ordinary paper, is small. For this reason, it is considered that high printing quality can be obtained. At the same time, it is considered that silica having high surface activity is not used or its usage can be reduced by the amount of the fiber fine powder, so that it is possible to suppress discoloration of printing. Further, by using a low-cost fiber fine powder, it is possible to reduce the cost of the inkjet recording material.

[0008] The basic component of the fiber fine powder or the fiber from which it originates is preferably one having ink absorbency. Typical are natural fibers, such as cellulose, cotton,
Silk, wool, chitosan and the like.

Approximately 300 dpi (dot per inch)
Considering that if the resolution is about 85 μm (the distance between the center of one dot and the center of the next dot), the average value of the length of the fiber fine powder is 85 μm, considering that the roughness of printing is less noticeable to human eyes. The following is preferred. If the length is longer than that, feathering becomes conspicuous, and the print quality deteriorates. 60 μm or less is more preferred, and 30 μm or less is even more preferred. At present, it is difficult to produce a fiber having a length of not more than tens of μm, and even a fine fiber powder having a lower limit in production can be effectively used. Inferring from the above mechanism, it is considered that even if a fiber fine powder having a shorter length can be produced in the future, it can be effectively used.

The length of the fibrous fine powder is determined by measuring the lengths of 50 fibrous fine powders present in a certain range of an image observed or photographed by an optical or electron microscope in the major axis direction and averaging them. Can be.

On the other hand, the diameter of the fiber fine powder is preferably 85 μm or less for the same reason as described above. However, in normal production, the diameter is smaller than the length, so that there is usually no problem if the length satisfies the above range.

Particles having a length and a diameter close to each other may be measured as a particle size, and the average particle size is preferably 85 μm or less. In this case, a commonly used particle size measuring method such as the method obtained from the above-mentioned microscopic observation or photographed image, centrifugal sedimentation method, Coulter counter method, laser scattering method and the like can be used.

The fiber fine powder used in the present invention may be produced by any production method. For example, ordinary fibers are fined to some extent by chemical or mechanical pretreatment, if necessary, and then crushed by mechanical pulverization, high-pressure dispersion treatment in water, or liquidized by dissolving or dispersing the fibers. Of the powder by a spray drying method or the like, or a method of chemically synthesizing.

The pigment component used in at least one of the ink receiving layers may be a fine fiber powder alone, but other pigments such as silica, alumina, calcium carbonate, resin particles, and various coloring pigments may be used in combination. May be. However, in order to exhibit the effect of suppressing the discoloration and fading of the print due to light or the like, it is necessary that the fiber fine powder is 20% of the entire pigment in the fiber fine powder containing layer.
It is necessary to be more than 50% by weight, and if it is more than 50% by weight, it is preferable that a non-specialized person can clearly sense discoloration and fading.

In order to fix the fiber fine powder on the base material or on the layer provided on the base material, a binder such as a resin may be used in combination.

Various resins and the like can be used as the binder, for example, PVA (polyvinyl alcohol), polyvinylpyrrolidone, CMC (carboxymethyl cellulose (sodium cellulose glycolate)), hydroxyethylcellulose, casein, gelatin , Starch and water-soluble resins such as sodium alginate, and emulsions of synthetic resins such as vinyl acetate, vinyl chloride-vinyl acetate copolymer, styrene-butadiene copolymer, polyurethane, acrylic copolymer, maleic acid copolymer, etc. Etc. are used.
These are appropriately selected and used alone or in combination for use.

When the pigment in the ink-jet ink is an anionic aqueous dye which is widely used at present, the aqueous dye is added to a fiber in order to further enhance the effect of suppressing discoloration of the print due to light or the like. It is effective to keep it in the fine powder containing layer. In order to retain more of this type of aqueous dye in the fine fiber powder-containing layer, it is effective to include a cationic substance in the fine fiber powder-containing layer.

In the case where the fiber fine powder-containing layer is formed on the outermost surface, or when the other layer provided on the fiber fine powder-containing layer has high transparency, a cationic substance is added to the fiber fine powder-containing layer. It is preferable to include a large amount of the aqueous dye in the fiber fine powder layer. In this case, since the aqueous dye stays in a large amount in a range visible from the surface, the print density is improved.

A cationic binder may be used as the binder. Specific examples of such a cationic binder include those in which an amine salt or an ammonium salt is bonded to the above-mentioned resin or the like, or those in which a component containing these functional groups is copolymerized. Can be

In addition to the binder, a cationic component,
For example, a cationized polymer generally called a cationizing agent may be used in combination. In this case, the binder is desirably nonionic or cationic. This is because when an anionic binder and a cationizing agent are used in combination, resin aggregation is likely to occur. Examples of the cationizing agent include low molecular weight compounds such as long-chain alkylamine salts, long-chain alkyldimethylamine salts, long-chain alkyltrimethylammonium salts, allylamine or salts thereof, diallyldimethylammonium salt, acrylic acid (or methacrylic acid) Dialkylaminoethyl or a salt thereof, acrylic acid (or methacrylic acid) trialkylammonium ethyl salt, homo- or copolymer such as diethylaminostyrene, or copolymer with other monomers, polyalkylene polyamines,
Dicyandiamide resin or the like can be used.

The amount of the cationized polymer or the like used separately from these binders depends on the selected pigment, binder and their ratio, but is usually 100% by weight based on the binder. Hereinafter, it is preferable to use 1% by weight or more based on the pigment. Usually, the cationized polymer is weak in strength, and if it is more than 100% by weight with respect to the binder, it is difficult to maintain the binding property. It becomes difficult to express the property. A more preferred range is 80% by weight based on the binder.
Hereinafter, it is 2% by weight or more based on the pigment.

The fiber fine powder or other pigment may be cationic. For example, a cationic pigment may be used separately from the fiber fine powder, or a fiber obtained by cationizing a fine fiber powder or another pigment may be used.

Examples of the cationic pigment include aluminum compounds such as alumina, aluminum hydroxide, and hydrated aluminum oxide, and those obtained by pulverizing the cationized polymer.

Examples of the cationizing treatment of the pigment include those obtained by attaching, depositing, doping, etc. the above aluminum compound to the surface or pores of fine fiber powder, inorganic pigment or organic pigment, amine salt or ammonium salt. Compounds obtained by chemically or physically adsorbing a compound containing a salt or the above-mentioned cationized polymer, or those obtained by converting a functional group on the surface or pores of an inorganic or organic pigment into a cationic functional group by a chemical reaction or the like Is mentioned.

The amount of the cationic pigment to be used may be selected based on the same standard (the ratio of the fine fiber powder in the pigment in the fine fiber powder-containing layer) as the amount of the pigment.

In the ink receiving layer including the layer using the fine fiber powder, in addition to the above components of the pigment, the binder, and the cationizing agent,
Various additives may be used as needed. For example, surface conditioner, defoamer, dispersant, viscosity modifier, water-proofing agent, cross-linking agent, coloring dye, fluorescent dye, fungicide, preservative, antistatic agent, lubricant, dusting inhibitor, water retention Agents and the like can be used.

The ratio of other components such as a binder and a cationic substance to the pigment component including the fine fiber powder is preferably 150% by weight or less in terms of solid content in order to obtain good ink absorbency. , 75% by weight or less is more preferable. If the binder has a high binding force, the content is more preferably 40% by weight or less. The ratio of the binder required to suppress the powder drop of the fiber fine powder greatly depends on the binding force of the binder,
Usually, it is preferably at least 3% by weight, more preferably at least 5% by weight.

In general, the thickness of the ink receiving layer including the layer using the fine fiber powder is preferably not less than 100 μm and not less than the thickness (≒ average diameter) in which the single layer of the fine fiber powder covers almost the entire surface. Below this range, it is difficult to obtain printability with little bleeding, and above the above range, the coating film tends to crack, and the portion below the ink receiving layer that does not contribute to ink reception increases, leading to unnecessary cost increases. Let it. A more preferable range is not less than the thickness (≒ average diameter) of the single layer of the fiber fine powder covering almost the entire surface and not more than 70 μm.

The ink receiving layer may have a layer structure of two or more layers, and a layer containing fine fiber powder may be used as a lower layer, an upper layer, or an intermediate layer. For example, a layer containing fiber fine powder is used as a lower layer, and a layer that gives a specific texture to the surface such as glossiness is provided as an upper layer, or a layer that provides high quality printing than a layer containing fiber fine powder is provided as an upper layer. May be. Examples of the pigment used in the layer other than the layer containing the fiber fine powder include pigments other than the fiber fine powder described above, cationic pigments, and the like. Preferred in terms of cost include silica, alumina, calcium carbonate and the like. Further, two or more layers containing fine fiber powder may be provided.

Considering that ink permeates from the surface, when the fiber fine powder is used for the upper layer, that is, the outermost layer,
In particular, when a cationic substance is contained in this layer, the effect of suppressing discoloration of the print due to light or the like can be exhibited most significantly.

As a substrate on which the ink receiving layer is provided, paper, paper,
Any shape such as a resin film or cloth that can be printed by an ink jet printer can be used. In particular, it is preferable to use a substrate having relatively high surface flatness and denseness, such as paper or film, because the uniformity of the surface of the provided ink receiving layer is enhanced and high-definition printing is possible. Various layers may be provided between these base materials and the ink receiving layer as needed. For example, an easy adhesion layer, an antistatic layer, a coloring layer, a vapor deposition layer, and the like can be given.

The ink receiving layer may be provided on one side or both sides of the substrate. Alternatively, the ink receiving layer may be provided on one surface of the substrate, and a different layer may be provided on the other surface. For example, an ink receiving layer, an antistatic layer, a coloring layer, a vapor deposition layer, an anti-curl layer, a layer for controlling slippage, a layer suitable for printing other than ink jet recording, a decorative layer, and the like can be provided as necessary.

The ink-jet recording material of the present invention may be manufactured by any manufacturing method, and a typical example will be described below.

First, if necessary, a surface treatment or a lower layer is applied to the base material, and a coating machine known in the art, such as a blade coater, an air knife coater, a reverse coater, a bar coater, a gravure coater, a die coater, etc., is applied thereon. A coating composition containing the above-mentioned fiber fine powder and a binder, and if necessary, the binder also contains a cationic component or another cationic component, and further contains other necessary components. Work and dry. Further, if necessary, the coating surface may be treated with a smoothing treatment machine, for example, a super calender, a gloss calender, a thermo punisher or the like to further improve smoothness.

Next, if necessary, one or more upper layers may be provided on a layer using fine fiber powder as a main component or one component of the pigment (fiber fine powder containing layer). However, the layer must not impair the printability of ink jet recording.
For example, a glossy layer, a layer capable of higher definition printing, a protective layer,
A UV absorbing layer or the like can be provided.

[0036]

Next, the present invention will be described in detail with reference to Examples and Comparative Examples, which are intended to specifically explain the effects of the present invention, and are not intended to limit the present invention. is not. In the following, “parts” means parts by weight.

<Example 1> 100 parts of ARBOCEL BE600-10 [J. RETTENMAER & SOHNE (here, "O" is umlaut O) GMBH + CO; Cellulose fine powder having an average length of 18 m and an average diameter of 15 m] Poval PVA-217 40 parts (Kuraray Co., Ltd .; polyvinyl alcohol) PAS-H-10L 10 parts (Nitto Boseki Co., Ltd .; cationizing agent) Water 575 parts

The above composition was mixed and stirred to obtain a surface layer coating material A having a solid content of 20%. Obtained surface layer paint A
Was coated and dried on a 85 g / m ² coated base paper using a # 44 bar coater to obtain an ink jet recording material.

Example 2 Poval PVA- of Example 1
An ink jet recording material was produced in the same manner as in Example 1, except that 217 was changed to 80 parts and PAS-H-10L was changed to 20 parts.

Example 3 Poval PVA- of Example 1
An ink jet recording material was produced in the same manner as in Example 1, except that 217 was changed to 16 parts and PAS-H-10L was changed to 4 parts.

Example 4 Poval PVA- of Example 1
217 to 14 parts, PAS-H-10L to 4 parts,
An ink jet recording material was produced in the same manner as in Example 1, except that Sumirez Resin 613 (manufactured by Sumitomo Chemical Co., Ltd .; water-proofing agent) was added in two parts.

Example 5 Poval PVA- of Example 1
217 was changed to 50 parts, and an ink jet recording material was produced in the same manner as in Example 1 except that PAS-H-10L was not used.

<Embodiment 6> ARBOCEL of Embodiment 5
An ink jet recording material was produced in the same manner as in Example 5, except that BE600-10 was changed to 80 parts and 20 parts of aluminum oxide C (manufactured by Nippon Aerosil Co., Ltd .; alumina having an average particle diameter of 13 nm) was added. .

<Embodiment 7> ARBOCEL of Embodiment 1
Changed BE600-10 to 60 parts, Carplex B
S-304F (manufactured by Shionogi & Co., Ltd .; average particle size: 17.5 μ)
m of silica) was added to prepare an inkjet recording material in the same manner as in Example 1 except that 40 parts of silica was added.

<Embodiment 8> ARBOCEL of Embodiment 1
An ink jet recording material was produced in the same manner as in Example 1, except that silk powder (fine powder of silk having an average particle diameter of 10 μm) was used instead of BE600-10.

<Embodiment 9> ARBOCEL of Embodiment 1
An ink jet recording material was produced in the same manner as in Example 1 except that wool powder (fine powder of natural wool having an average particle diameter of 15 μm) was used instead of BE600-10.

<Comparative Example 1> ARBOCEL of Example 1
Carplex BS-30 instead of BE600-10
An ink jet recording material was produced in the same manner as in Example 1 except that 4F was used.

<Comparative Example 2> ARBOCEL of Example 7
40 copies of BE600-10, Carplex BS-30
An ink jet recording material was produced in the same manner as in Example 7, except that 4F was changed to 60 parts.

<Comparative Example 3> ARBOCEL of Example 1
ARBOCEL BE00 instead of BE600-10
Example 1 (Rettenmeyer; cellulose fine powder having an average length of 120 μm and an average diameter of 20 μm) was used.
In the same manner as in the above, an ink jet recording material was produced.

<Comparative Example 4> ARBOCEL of Example 5
Carplex BS-30 instead of BE600-10
An ink jet recording material was produced in the same manner as in Example 1 except that 4F was used.

Using the ink jet recording materials obtained in Examples 1 to 9 and Comparative Examples 1 to 4 as test samples, each of the following measurement items was measured by the corresponding measurement method. Table 1 summarizes the results.

<Measurement Items and Test Methods> Printing characteristics: Epson printer PM on the outermost surface
Using a special glossy paper as a print mode using -2000C, black (K), cyan (C), magenta (M),
Solids of yellow (Y), C + M, M + Y, and C + Y were printed, and the following characteristics were evaluated. The ink absorption and drying properties were both good.

1-1 Print density: 24 hours after printing, the density of the designated print portion was measured by Macbeth densitometer RD915.

1-2 Bleeding: Observing the edge of the print, it was confirmed that there was no bleeding and the sharpness was 5 and that the bleeding caused the feathering or swelling around 0.5 mm or more. As one, the evaluation was made in five steps.

1-3 Water resistance: One drop of water was dripped at the edge of the print and rubbed with a finger, and the appearance of the print and the coating film was observed.

2. Discoloration / fading property: The above printed sample is irradiated with a xenon weatherometer (light source: xenon 6.5 kW) for 24 hours, and the color before and after printing and the background color are measured by a color difference meter BYK-G.
L ^* , a using color-guide manufactured by Ardner
^{* And} b ^* values, and the discoloration degree ΔE was determined by the following equation. The smaller the value, the smaller the discoloration.

ΔE = [(ΔL ^* ) ² + (Δa ^* ) ² +
(Δb ^* ) ² ] ^1/2

[0058]

[Table 1]

As is clear from the results of the above test, the quality of the embodiment of the ink jet recording material of the present invention using the low-cost fiber fine powder is the print quality comparable to the quality of the comparative example. It turns out that it is very excellent in discoloration degree.

[0060]

As described above, according to the ink-jet recording material of the present invention and the method of manufacturing the same, a low-cost ink-jet recording material with little discoloration of printing due to light or the like can be obtained.

Claims (11)

[Claims] 1. An ink jet recording material having an ink receiving layer comprising one or more layers on at least one surface of a substrate, wherein a main component of a pigment in at least one layer constituting the ink receiving layer is provided. Alternatively, as one component, an ink jet recording material comprising a fine fiber powder in an amount of 20% by weight or more based on the total amount of the pigment contained in the layer. 2. In an ink jet recording material having an ink receiving layer composed of one or more layers formed on at least one surface of a substrate, a main component of a pigment in at least one layer constituting the ink receiving layer Alternatively, as one component, an ink jet recording material characterized in that fine fiber powder is contained in an amount of 50% by weight or more based on the whole pigment contained in the layer. 3. The ink jet recording material according to claim 1, wherein the layer containing fine powder of fibers as a main component or one component of the pigment contains a cationic substance. 4. The ink jet recording material according to claim 3, wherein the cationic substance is a compound containing an amine salt or an ammonium salt. 5. The ink jet recording material according to claim 3, wherein the cationic substance is an aluminum compound or a powder treated with an aluminum compound. 6. The ink jet recording material according to claim 5, wherein the aluminum compound comprises one or more of alumina, aluminum hydroxide, and hydrated aluminum oxide. 7. The ink-jet recording material according to claim 1, wherein the average value of the length or particle size of the fine fiber powder is 100 μm or less. 8. The ink jet recording material according to claim 1, wherein the fine fiber powder is made of one or more of fine powders of cellulose, cotton, silk, wool, and chitosan. 9. The ink jet recording material according to claim 1, wherein the substrate is paper or a resin film. 10. One or more of silica, alumina and calcium carbonate are used as the main component or one component of the pigment on the layer using the fine powder of fiber as the main component or one component of the pigment. The inkjet recording material according to any one of claims 1 to 9, further comprising a layer. 11. The fine fiber powder and the binder according to claim 1 on at least one surface of the substrate or on at least one surface of the substrate provided with the lower layer. A method for producing an ink jet recording material, comprising applying a paint containing the composition and drying the composition.