JP2001262480A - Image receptor for recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image receptor for recording which is useful in an ink-jet recording system and is excellent in seeing through property from the surface not undergoing image formation, feeling, ink absorptivity, the clarity of a recorded image, water resistance and durability. SOLUTION: This image receptor for recording is prepared by applying to a porous substrate an organic acid having a solubility to 100 g water at 20 deg.C of 0.01-2 g, and has a haze value measured by following JIS K 7,125 of >=30% and a ratio (ODb/ODs) [wherein ODs is color strength on a surface undergoing image formation; and ODb is color strength on a surface not undergoing image formation] of >=0.7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is useful in an ink jet recording system and is excellent in transparency, texture, ink absorption, clarity of recorded images, water resistance and durability from the non-image forming side. The present invention relates to an image receiver.

[0002]

2. Description of the Related Art Ink-jet recording systems have been rapidly spreading in recent years because they can be easily converted to full color, have low noise, have good printing quality, and are economical. Used in wide printers for sign displays. In ink-jet recording, water-based inks are generally mainly used. However, since the water-based ink is hard to dry and fix, the recording portion is apt to be stained, and the quality of the recorded image or character is likely to be deteriorated.

In order to solve these problems, it has been proposed to provide a porous layer as an ink absorbing layer and to absorb the ink by a capillary phenomenon. For example, Japanese Patent Application Laid-Open
JP-A-110287 and JP-A-5-51470 disclose a recording sheet in which fine particles such as silica are aggregated and a porous layer having pores formed by gaps between the particles is provided on a support. Proposed. These recording sheets have improved ink absorbency, but do not have sufficient ink absorption capacity and are not suitable for applications requiring a soft texture.

On the other hand, when ink-jet recording is performed on textiles such as cloth having a soft texture, the above-mentioned ink-absorbing layer is provided or the ink-absorbing layer containing the hot-melt adhesive resin of the recording sheet is thermally transferred. The method has been done. However, the texture of the cloth is reduced by the ink absorbing layer. Furthermore, in opaque sheets and textiles, among the sheets and cloths, the opaque sheets and cloths have an ink absorbing layer, so that a clear image can be formed on the image forming surface, but from the non-image forming side. Cannot see through the image, which limits its use. On the other hand, a sheet or cloth having excellent transparency from the non-image forming surface side is inferior in the clarity, texture, water resistance, durability and the like of the recorded image.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a recording image receiving body which can form a clear image on an image forming surface and can also see through the image from a non-image forming surface side. It is in.

Another object of the present invention is to provide a recording image receiving body having high ink absorbency without impairing the feeling.

It is still another object of the present invention to provide a recording image receiving member having excellent water resistance and durability without forming an ink absorbing layer.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the above object, and as a result, have a specific haze value, and have a color density difference between an image forming surface and a non-image forming surface. It has been found that by using a small number of recording image receiving members, it is possible to obtain a recording image receiving member having excellent transparency and texture from the non-image forming surface side, and completed the present invention.

That is, the recording image receiving body of the present invention is a JI
A haze value measured according to SK 7125 is 30% or more, and a sheet-like image receiving body for forming an image, wherein the color density (ODs) of the image forming surface and the color density of the non-image forming surface (ODb) and the ratio (ODb / ODs) to 0.
7 or more (preferably 0.8 to 1). The recording image receiver may have a total light transmittance of 30% or more (preferably 40% or more) measured according to JIS K 7125. The recording image receiver may be formed of a fibrous support (in particular, a nonwoven fabric). The recording image receiver,
It may be composed of a porous support to which an organic acid having a solubility in water of 100 g at 20 ° C. of 2 g or less is adhered. The recording image receiver had no ink absorbing layer and had a solubility in water of 100 g at 20 ° C. of 2 g.
A sheet-like image receiver for forming an image by an ink jet recording method, which is formed of a flexible nonwoven fabric to which the following organic acid is adhered, and has a haze value of 50 to 95% measured according to JIS K 7125. , The total light transmittance is 5
0 to 80% and the color density (OD
s) and the color density (ODb) of the non-image forming surface (ODb)
/ ODs) may be about 0.9 to 1. The basis weight of the nonwoven fabric may be about 40 to 100 g / m ² .

The present invention also includes a method for producing the above-mentioned recording image-receiving body by adhering an organic acid having a solubility in 100 g of water at 20 ° C. of 2 g or less to a porous support. The present invention also includes a method for using the recording image receiving body for inkjet recording.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION [Support] A sheet (or film) having a haze value of 30% or more of a recording receiver as measured according to JIS K 7125 as a support constituting the recording receiver. There is no particular limitation on the shape of the image receiver, and examples thereof include a fibrous support and a plastic sheet (or film). Among these supports, a porous support such as a fibrous support or a porous plastic sheet is preferable from the viewpoint of excellent ink absorbability. When a porous support is used, it is not necessary to form an ink absorbing layer on a sheet, so that the texture is not impaired.

Examples of the fibrous support include cloths (woven cloth or non-woven cloth) and papers. The fibrous support has a texture in which the fibers are randomly or regularly entangled. Papers or nonwovens usually have a papermaking or web structure.

The type of woven or non-woven fabric (the type of raw material) is not particularly limited as long as the ink absorbency is not impaired. For example, fibers (natural fibers, regenerated fibers, semi-synthetic fibers, synthetic fibers, etc.) Can be produced by a conventional method (for example, a method of forming fibers into a web for a nonwoven fabric, such as a method of bonding by thermocompression bonding or an adhesive, a needle punching method, a papermaking method, etc.).

Examples of natural fibers include cotton, hemp, silk, wool, and cellulose fibers. Rayon (such as viscose rayon) is exemplified as the recycled fiber.
Examples of the semi-synthetic fibers include cellulose ester fibers (such as cellulose acetate fibers). As synthetic fibers, polyester fibers (polyethylene terephthalate fibers, polybutylene terephthalate fibers, etc.), (meth) acrylic fibers (poly (meth) acrylate ester fibers, polyacrylonitrile fibers, etc.), polyamide fibers (nylon 6 fibers, Nylon 66 fiber), polyolefin fiber (polyethylene fiber, polypropylene fiber, etc.), halogen-containing vinyl fiber (polyvinyl chloride fiber, polyvinylidene chloride fiber, vinyl chloride-vinyl acetate copolymer fiber, vinyl chloride-acrylonitrile copolymer) Coalesced fibers), polyvinyl alcohol-based fibers, polyurethane-based fibers, polyclar fibers, fluorine-based fibers, and the like. These fibers can be used alone or in combination of two or more.

Preferred fibers include cellulose ester fibers, polyester fibers (polyethylene terephthalate fibers, polybutylene terephthalate fibers, etc.), polyolefin fibers (polyethylene fibers, polypropylene fibers, etc.), polyamide fibers, especially polyester fibers.

The basis weight of the woven or nonwoven fabric is, for example, 30
g / m ² or more, preferably 40 g / m ² or more (for example,
0-1000 g / m ² ), more preferably 40-50
0 g / m ² (e.g., 40~100g / m ²⁾ it is about. The average fiber diameter is, for example, about 0.01 to 100 μm, preferably about 0.1 to 50 μm (particularly 1 to 10 μm). The air permeability is about 0.1 to 100 cm ³ / cm ² · s, and preferably about 0.1 to 50 cm ³ / cm ² · s.

Examples of papers include papers (print papers such as high-quality paper, medium-quality paper, finely-upgraded paper, paper-breaking paper, Kent paper), wrapping papers such as kraft paper and roll paper, thin papers such as glassine paper and Indian paper. Etc.), synthetic papers (various synthetic papers using polypropylene, polystyrene, etc.), chemical fiber papers (various chemical fiber papers using chemical fibers such as polyester fibers as raw materials), plastic sheets (or films) and the like. The polymer constituting the porous plastic sheet is not particularly limited as long as it has high wettability to the ink, and various resins (a thermoplastic resin and a thermosetting resin) can be used. used. Examples of the thermoplastic resin include a polyester resin, a vinyl resin, a cellulose derivative, a polycarbonate resin, a polyamide resin, a polysulfone resin, and a thermoplastic polyurethane resin.

Among these porous supports, a fibrous support (for example, cloth), particularly a non-woven fabric (for example, polyester non-woven fabric) is preferred from the viewpoint of excellent texture (flexibility), water resistance, durability and the like. .

The average pore size on the surface and inside of the porous support is about 0.005 to 10 μm, preferably 0.01 to 8 μm.
It can be selected from the range of about μm, more preferably about 0.01 to 5 μm (for example, 0.01 to 3 μm). When the average pore size is in the above range, the ink absorbency, water resistance, and clarity (print quality) of a recorded image are excellent.

The ink absorption is also affected by the porosity of the porous support. The porosity of the porous support can be selected from the range of about 40 to 80%, preferably about 42 to 75%. When the porosity is in the above range, the ink absorbency is excellent without forming an ink absorbing layer.

The thickness of the porous support is usually, for example, about 20 to 200 μm, preferably 50 to 200 μm, in consideration of forming an image by inserting the porous support into an ink jet printer.
About 170 μm, more preferably 80 to 150 μm
It is about.

Further, the porous support may contain a conventional additive,
For example, crosslinking agents, curing agents, defoamers, coating improvers, thickeners, lubricants, stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), dyes, pigments, antistatics Agents, anti-blocking agents, fillers, gelling agents and the like.

[Organic acid] An organic acid may be attached to the support. The organic acid may be attached to the surface and / or the inside of the support.

The organic acid has a solubility in 100 g of water at 20 ° C. of 2 g or less (eg, 0.01 to 2 g), preferably 1.5 g or less (eg, 0.01 to 1.5 g).
It is about. By attaching the organic acid to the porous support, the sharpness of the recorded image can be improved.

The organic acids include aromatic polycarboxylic acids (C _8-12 aromatic polycarboxylic acids such as phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid, and acid anhydrides thereof). Products), aromatic sulfonic acids (benzenesulfonic acid, o-toluenesulfonic acid,
C _6-10 aromatic polycarboxylic acids such as m-toluenesulfonic acid, p-toluenesulfonic acid, naphthalene-α-sulfonic acid, naphthalene-β-sulfonic acid, etc.), alicyclic polycarboxylic acids (1,4- _C8-10 alicyclic polycarboxylic acids such as cyclohexanedicarboxylic acid and tetrahydrophthalic acid, etc.), and heterocyclic polycarboxylic acids (pyridinecarboxylic acid,
Pyridine tricarboxylic acid, pyridine tetracarboxylic acid, etc.), aliphatic polycarboxylic acids (glutaric acid, adipic acid, suberic acid, such as C _2-10 fatty acids saturated polycarboxylic acids such as sebacic acid, C _4-6 aliphatic such as itaconic acid Group-unsaturated polycarboxylic acids, etc.). Of these organic acids, phthalic acids and their derivatives are preferred.

The above-mentioned organic acid can be used as a salt, and part or all of the carboxyl group or sulfonic acid group of the organic acid may form a salt with a base. The organic acid salt includes a salt with an inorganic base (eg, an alkali metal such as ammonia, potassium, and sodium) and a salt with an organic base (eg, a tertiary amine).

The organic acid is applied to the support at a dry adhesion amount of 0.05 g / m ² or more (for example, 0.05 to 1 g / m ^2).
m ² ), preferably 0.1 g / m ² or more (eg, 0.1 g / m ²
１1 g / m ² ), more preferably 0.2 to 0.8 g / m ²
m ² may be adhered.

The organic acid is an additive such as a dye fixing agent,
Stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), binders (water-insoluble hydrophilic resins such as cellulose ester, polyester, acrylic resin, polyamide, polysulfone, polyurethane, etc.), coloring It may be used together with an agent, an antistatic agent, an antifoaming agent, a coating improver, a thickener, a lubricant, a dye / pigment, an antiblocking agent, a filler, a gelling agent and the like.

[Recording Receiver] The recording receiver of the present invention has a ratio (ODb / ODs) of the color density (ODs) of the image forming surface to the color density (ODb) of the non-image forming surface. 0.7 or more (for example, 0.7 to 1), preferably about 0.8 to 1, and more preferably about 0.85 to 1 (for example, 0.9 to 1). When the ratio between ODs and ODb is 0.7 or more,
Since the transparency from the non-image forming surface side is excellent, the image can be well recognized from the non-image forming surface side. Note that the color density (ODs) of the image forming surface is the color density of the image forming portion on the image forming surface, and the color density (ODb) of the non-image forming surface is the opposite of the image forming surface. This is the color density of a portion of the surface corresponding to the image forming section.

The recording receiver is JIS K71.
The haze value measured according to 25 is 30% or more (for example, 30 to 99%), preferably 50% or more (for example,
50-95%), more preferably 70% or more (for example, 70-95%), particularly 80% or more (for example, 80-95%).
93%).

Further, the total light transmittance measured according to JIS K 7125 is 30% or more (for example, 30 to 9).
5%), preferably 40% or more (for example, 40 to 90%).
%), More preferably 50% or more (for example, 50 to 8%).
0%). When the total light transmittance is 30% or more, the haze value is high, and even an opaque (or translucent) image receiver can easily see an image from the non-image forming surface side.

Since the recording image receiving body of the present invention is excellent in water absorbency, for example, an ink jet recording image receiving sheet for recording by discharging small droplets of ink (eg, pigment type aqueous ink and dye type aqueous ink). May be used. The recording image receiving body of the present invention can be used indoors and outdoors, but when used outdoors, pigment-type aqueous inks are frequently used from the viewpoint of durability. In addition, among the ink-jet recording image receiving bodies, the present invention can be used particularly for applications requiring transparency and texture (flexibility) from the non-image forming surface side, for example, flags, banners, and curtains.

[Production Method] The recording image receiving body of the present invention can be composed of a support, particularly a porous support. In a preferred embodiment, the organic acid having solubility described above is attached to the porous support. Can be manufactured. For details,
A conventional method, for example, a method of impregnating the porous support with the solution containing the organic acid and drying, or a method of applying the solution containing the organic acid to the porous support and drying the solution can be used. . The application method is not particularly limited, and roll coating, air knife coating, blade coating,
Known methods such as a rod coating, a bar coating, and a comma coating method can be applied.

The solvent of the impregnating or coating solution can be selected according to the kind of the organic acid and the like, and is not particularly limited. For example, alcohols (eg, C _1-4 alkyl alcohols such as methanol, ethanol, isopropanol, and butanol), ketones (eg, di-C _1-4 alkyl ketones such as acetone and methyl ethyl ketone), and esters (eg, formic acid C such as ethyl formate) _1-4 alkyl esters, ethers (cyclic or linear C _4-6 ethers such as 1,4-dioxane and tetrahydrofuran), cellosolves (C _1-4 alkyllosolves such as methyl cellosolve and ethyl cellosolve). And aromatic hydrocarbons (benzene, toluene, xylene, etc.). These solvents may be used as a mixed solvent. Further, the impregnating or coating solution may be a solvent containing water. The concentration of the impregnating or coating solution is as follows: organic acid / solvent (weight ratio) = 0.1 / 99.9 to 10/90
(0.1 / 99.9-20 / 80), preferably 1/9
It is about 9 to 10/90.

[0035]

According to the present invention, it is possible to obtain a recording image receiving body that can form a clear image on the image forming surface and can also see through the image from the non-image forming surface side. Further, a recording image receiver having high ink absorbability can be obtained without impairing the texture. Further, a recording image receiving member having excellent water resistance and durability can be obtained without forming an ink absorbing layer.

[0036]

The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples.

Parts and percentages are by weight unless otherwise specified. The haze value and the total light transmittance of the recording image receivers obtained in Examples and Comparative Examples were measured according to JIS K.
The measurement was performed according to 7125, and the color density of the front and back surfaces, the clarity of the front and back surfaces, the water resistance, and the strength were evaluated as follows.

[Color density on front and back surfaces] Ink jet printer (NOVAJET PR, manufactured by ENCAD)
Using O), a pigment-type aqueous ink (each color of yellow, magenta, cyan, and black) was solidly printed on the recording image receiving bodies obtained in Examples and Comparative Examples to form recorded images. The color density of this recording portion was measured on the image forming surface (front surface) and on the non-image forming surface (back surface) using a Macbeth color densitometer. Of the color density data of the image receiving bodies obtained in Examples and Comparative Examples, the color density of magenta is shown in Table 1 as a representative, and the front surface is represented by ODms and the back surface is represented by ODmb.

[Clearness of Front and Back Sides] After performing the same printing as in the color density test on the recording receivers obtained in Examples and Comparative Examples, the appearances of the front and back sides of the receivers are visually observed. Then, the sharpness was evaluated according to the following criteria. The sharpness of the front surface and the back surface was defined as sharpness s and sharpness b, respectively.

◎: no bleeding, very clear ○: slight bleeding ×: severe bleeding

[Water resistance] The recording receivers obtained in Examples and Comparative Examples were printed in the same manner as in the above color density test, immersed in water at room temperature for 24 hours, and then changed in appearance according to the following criteria.
It was evaluated visually.

◎: No abnormality 若干: Slight elution of the image part ×: Most of the image part eluted.

[Outdoor Durability] The recording receivers obtained in Examples and Comparative Examples were cut into a size of 2 m in length and 2 m in width, and formed into a metal rod having one side of the receiver perpendicular to the ground. ,
It was fixed to a height of 2 m from the ground and left outdoors for one week. The appearance of the image receiver after one week was visually evaluated according to the following criteria.

◎: No abnormality 破: Torn is observed X: Most of the pieces are torn from metal rods.

Example 1 Polyester nonwoven fabric (manufactured by Hirose Paper Co., Ltd., "05-TH
60 ", a basis weight of 60.0 g / m ² , a thickness of 110 μm, a haze value of 89.3% and a total light transmittance of 46.2%) were impregnated with the solution a shown below, and dried at 80 ° C. for 5 minutes. Thus, a recording image receiver having a dry adhesion amount of phthalic acid of 0.7 g / m ² was obtained. Table 1 shows the evaluation results of the image receiver.

[Solution a] A solution a was prepared by mixing 5 parts of phthalic acid and 95 parts of isopropanol as a solvent.

Example 2 Polyester nonwoven fabric (manufactured by Hirose Paper Co., Ltd., "15-TH
48 ", a basis weight of 48.0 g / m ² , a thickness of 110 µm, a haze value of 86.1% and a total light transmittance of 60.1%) were impregnated with the solution a and dried at 80 ° C for 5 minutes to obtain phthalate. A recording image receiver having an acid dry adhesion of 0.6 g / m ² was obtained.
Table 1 shows the evaluation results of the image receiver.

Comparative Example 1 Polyester cloth (manufactured by Toyobo Co., Ltd., “T1116”)
4 ", 92.3 g / m ^Two, Thickness 420μm, haze
Value 90.3%, total light transmittance 31.3%)
impregnated in a and dried at 80 ° C for 5 minutes to dry phthalic acid
1.1 g / m^TwoWas obtained. Of the receiver
Table 1 shows the evaluation results.

Comparative Example 2 Ink-jet compatible PPC paper (manufactured by Kishu Paper Co., Ltd.)
"FC Dream", 82.0 g / m ² in weight, 88μ in thickness
m, haze value 89.4%, total light transmittance 36.8%)
Was impregnated with the above solution a and dried at 80 ° C. for 5 minutes to obtain a recording image receiver having a dry adhesion amount of phthalic acid of 0.6 g / m ² . Table 1 shows the evaluation results of the image receiver.

[0050]

[Table 1]

As is clear from Table 1, Examples 1 and 2
The image receiving body obtained in the above has sufficiently high color densities on the front surface and the rear surface and a small color density difference. Further, since the sharpness of the front and back surfaces is also very good, the visibility of both surfaces is sufficient. On the other hand, since the image receiving body of Comparative Example 1 has a thick substrate, the ink stays inside the substrate, the color density on the back surface is low, and the visibility on both sides is low. Further, the image receiving body of Comparative Example 2 has slightly better double-side visibility, but is inferior in water resistance and strength.

Claims (10)

[Claims] 1. A sheet-shaped image receiving body having a haze value measured according to JIS K 7125 of 30% or more and forming an image, wherein the color density (OD) of the image forming surface is
s) and the color density (ODb) of the non-image forming surface (ODb)
/ ODs) is 0.7 or more. 2. The recording image receiving body according to claim 1, wherein the ratio between ODs and ODb is 0.8 to 1. 3. The recording image receiving body according to claim 1, wherein the total light transmittance measured according to JIS K 7125 is 30% or more. 4. The recording image receiving body according to claim 1, wherein the total light transmittance measured according to JIS K 7125 is 40% or more. 5. The recording image receiver according to claim 1, wherein the image receiver is formed of a fibrous support. 6. The recording image receiver according to claim 5, wherein the fibrous support is a nonwoven fabric. 7. The recording image receiving member according to claim 1, wherein the image receiving member comprises a porous support to which an organic acid having a solubility in 100 g of water at 20 ° C. of 2 g or less is adhered. 8. An ink-absorbing layer is not formed, and 20
A sheet-shaped image receiving body for forming an image by an ink jet recording method, which is formed of a flexible nonwoven fabric to which an organic acid having a solubility in water of 100 g or less at 100 ° C. is 2 g or less, and which is measured according to JIS K 7125. Haze value is 50-95% and total light transmittance is 50-80%
And the ratio (ODb / ODs) between the color density (ODs) of the image forming surface and the color density (ODb) of the non-image forming surface.
Is 0.9 to 1. 9. The nonwoven fabric has a basis weight of 40 to 100 g / m.
9. The recording image receiving body according to claim 8, wherein the number is ² . 10. Water 1 at 20 ° C. is added to a porous support.
2. The method for producing a recording image receiving body according to claim 1, wherein an organic acid having a solubility in 00 g of 2 g or less is adhered.