JP2001191634A - Recording image receiver and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording image receiving member excellent in ink absorption, blocking resistance, texture, surface gloss, clarity of recorded image, color reproducibility, water resistance and weather resistance. SOLUTION: On at least one surface of the porous support,
The solubility in water of 100 g at 20 ° C. is 0.01 to
2 g of an organic acid is adhered to prepare a recording image receiver.
The organic acid may adhere in an amount of 0.05 g / m ² or more on a dry basis. The porous support may be a porous plastic sheet, a woven fabric, a nonwoven fabric, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording receiver and a method for manufacturing the same. More particularly, the present invention relates to a recording image receiving body excellent in ink absorbency, blocking resistance, texture, surface gloss, clarity of recorded images, color reproducibility, water resistance and weather resistance in an ink jet recording system, and a method for producing the same.

[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 inkjet recording, to prevent clogging of the ink jet nozzle,
Inks having low drying properties are required, and water-based inks are generally used mainly in view of safety and recording suitability. The ink is ejected from the ejection head toward the recording image receiving body as small droplets, and the recording image receiving body is required to quickly absorb the ink and record an image.

For example, in a recording receiver having a low ink absorbency, the ink remains on the surface of the receiver without being dried and fixed for a long time even after the recording is completed. If touched or overlapped, the recording area will be stained with ink that has not been dried and fixed. Further, in the high-density image area, a large amount of supplied ink is not absorbed, and the inks of the respective colors are mixed to deteriorate the quality of the recorded image or character or to flow out on the surface of the recording receiver.

Some proposals have been made to solve these problems. For example, JP-A-59-
174381 and JP-A-60-224578 propose that an ink receiving layer is formed on a support using a hydrophilic polymer such as starch, a water-soluble cellulose derivative, or polyvinyl alcohol. However, in this recording receiver, even if the ink absorbing property is satisfied, the water resistance of the ink receiving layer itself is low, and the ink receiving layer and the recording portion are dissolved in water, the surface is viscous, and the sheets are stacked. Causes blocking.

Further, Japanese Patent Publication No. 3-72460 discloses that
There has been proposed a method comprising a combination of an ink-permeable surface layer and an ink-absorbing underlayer, wherein the ink is absorbed by the underlayer and blocking resistance is improved by the surface layer. However, since the ink passes through the surface layer and is absorbed by the underlayer, the ink penetrates deeply into the recording sheet, making it difficult to increase the color density of the recorded portion. Are easily peeled off, and the water resistance of the underlayer is low.

It has also been proposed to provide a porous layer as an ink absorbing layer to absorb ink by capillary action. For example, JP-A-58-110287,
JP-A-5-51470 proposes 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. These recording sheets have improved ink absorption, but have low surface gloss due to light scattering of particles, and have insufficient ink absorption capacity.

Furthermore, Japanese Patent Application Laid-Open No. 61-86251 proposes a recording sheet in which a porous plastic thin film layer is laminated on an ink absorbing layer, but the porous plastic thin film is made of a hydrophobic material such as polyethylene or polypropylene. Because it is formed of plastic, ink permeability is not sufficient in ink jet recording in which water-based ink is mainly used, and because a porous plastic thin film is laminated by a thermocompression method, holes are crushed, Deform.

On the other hand, when ink-jet recording is performed on textiles such as cloth, the above-mentioned ink absorbing layer may be provided,
A method of thermally transferring an ink absorbing layer containing a hot melt adhesive resin of a recording sheet has been used. However, the texture of the cloth is reduced by the ink absorbing layer.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a recording image receiving body which is excellent in ink absorbency and blocking resistance, and which is excellent in texture, and a method for producing the same.

Another object of the present invention is to provide a recording image receiving body capable of greatly improving the surface gloss, the sharpness of a recorded image and the color reproducibility, and a method of manufacturing the same.

Still another object of the present invention is to provide a recording image receiving body having excellent water resistance and weather resistance of a recorded image, and a method for producing the same.

[0012]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, when a specific organic acid is adhered to at least one surface of a porous support, a recording image receiving image is obtained. It has been found that the ink receiving property of the ink can be improved and the blocking resistance can be improved, and a recording image receiving body having an excellent texture can be obtained, and the present invention has been completed.

That is, the recording image-receiving member of the present invention is characterized in that at least one surface of the porous support is coated with water at 20 ° C.
An organic acid having a solubility of 0.01 to 2 g with respect to 00 g is attached. The dry adhesion amount of the organic acid is usually 0.05
g / m ² or more. The porous support may be a porous plastic sheet, cloth (woven cloth or nonwoven cloth) or the like.

The present invention also includes a method for producing a recording image receiving body in which the organic acid having solubility is attached to at least one surface of a porous support. The attachment may be performed by coating, impregnation, or the like.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The recording image receiving body of the present invention has a structure in which water at 20 ° C. is coated on at least one surface of a porous support.
An organic acid having a solubility in 0 g of 0.01 to 2 g is attached.

[Porous support] As the porous support,
There is no particular limitation, and examples thereof include a porous plastic sheet and a fibrous support.

The polymer constituting the porous plastic sheet is not particularly limited as long as it has high wettability to ink, and various resins (thermoplastic resin and thermosetting resin) can be used. A plastic resin is used. Examples of the thermoplastic resin include the following polymers.

(1) Polyester polymer: polyalkylene terephthalate (for example, 1,4-cyclohexane dimethylene terephthalate, ethylene terephthalate,
Homo or copolyester containing butylene terephthalate, etc., polyalkylene naphthalate (for example, homo or copolyester containing ethylene naphthalate or butylene naphthalate), etc.

(2) Vinyl polymers: olefin polymers [for example, olefin homopolymers or copolymers (polyethylene, polypropylene, poly 1-butene, polyisobutene, polybutadiene, polyisoprene, polyarene, ethylene-propylene copolymer) Etc.), copolymers of olefins and copolymerizable monomers (ethylene-vinyl acetate copolymer, ethylene- (meth) acrylate copolymer,
Modified polyolefin, etc.) Halogen-containing vinyl polymer [eg, a homo- or copolymer of halogen-containing vinyl monomer (eg, polyvinyl chloride), a copolymer of halogen-containing vinyl monomer and copolymerizable monomer ( Vinyl chloride-vinyl acetate copolymer, vinylidene chloride-vinyl acetate copolymer, vinylidene chloride- (meth) acrylic acid copolymer, vinylidene chloride- (meth) acrylic acid ester copolymer, etc.)] vinyl ester polymer Or a derivative thereof [e.g., polyvinyl acetate, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinyl acetal polymer (polyvinyl formal, polyvinyl acetal, polyvinyl butyral, etc.)] Heterocyclic vinyl polymer [polyvinyl pyrrolidone, polyvinyl Pyridine etc.] Aromatic vinyl polymer [Example If, styrene polymer (polystyrene, rubber-reinforced polystyrene, ABS resin, etc.), a copolymer of an aromatic vinyl monomer and a copolymerizable monomer (styrene - (meth) acrylic acid C
_1-10 alkyl ester copolymer, styrene-maleic anhydride copolymer, styrene-maleimide copolymer, etc.)] Allyl alcohol-based polymer (for example, allyl alcohol-C _1-6 alkyl vinyl ether copolymer) polyvinyl ketone Classes [eg, polyvinyl methyl ketone, polyvinyl methyl isobutyl ketone, polymethyl isopropenyl ketone, etc.] Vinyl ether polymers [eg, polymethyl vinyl ether, methyl vinyl ether-maleic anhydride copolymer, etc.] (meth) acrylic polymers [ For example, homo- or copolymers of (meth) acrylic monomers ((meth) acrylonitrile, (meth) acrylate monomers, etc.), (meth)
Acrylic monomer and copolymerizable monomer (vinyl monomer such as vinyl ester monomer, heterocyclic vinyl monomer, aromatic vinyl monomer, polymerizable unsaturated dicarboxylic acid or derivative thereof) And a copolymer with

(3) Cellulose polymer (cellulose derivative): Cellulose ester [for example, organic acids such as cellulose acetate (cellulose acetate), cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, etc. Esters; inorganic acid esters such as cellulose nitrate, cellulose sulfate and cellulose phosphate; mixed acid esters such as cellulose nitrate acetate; etc.] Cellulose ethers [eg, methyl cellulose, ethyl cellulose, isopropyl cellulose, butyl cellulose, benzyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, Carboxyethylcellulose, cyanoethylcellulose, etc.]

(4) Polycarbonate polymer: 2,2
-Polymer obtained by reaction of dihydroxy compound such as bis (4-hydroxyphenyl) propane (bisphenol A) with diester carbonate such as phosgene or dimethyl carbonate

(5) Polyamide-based polymer: aliphatic polyamide (for example, nylon 6, nylon 66, nylon 6
10, nylon 612, nylon 11, nylon 12
etc)

(6) Polysulfone-based polymer: a polymer having a bonding group -SO _2-in its molecule, such as polysulfone (eg, polyhexamethylene sulfone), sulfonated polysulfone, polyether sulfone, etc.

(7) Polyurethane polymer: a polymer obtained by reacting a polyol with a polyisocyanate such as polyethylene glycol such as tolylene diisocyanate and a polyol.

(8) Polymer derived from epoxide:
Polyalkylene glycols (for example, polyethylene glycol and polypropylene glycol) and epoxy resins (for example, ether-based epoxy resins such as bisphenol-type epoxy resins and novolak-type epoxy resins, and amine-based epoxy resins), and copolymers and blends thereof. Crosslinked products can also be used. Among these, from the viewpoint of mechanical strength, workability, etc., polyester-based polymers,
Particularly, a polyalkylene arylate polymer such as polyethylene terephthalate can be preferably used. These polymers can be used alone or in combination of two or more kinds as a single layer sheet or a laminated sheet.

For the porous plastic sheet, for example, a phase separation method in which a polymer is microphase-separated using a good solvent and a poor solvent, a foaming method in which a polymer is foamed to form pores, and a stretching treatment of a polymer film Stretching method, radiation irradiation method to irradiate the polymer film with radiation to form pores, from a film consisting of a polymer or inorganic salts soluble in a solvent and a polymer insoluble in the solvent, soluble in the solvent It can be produced by an extraction method in which pores are formed by extracting and removing essential components, or a sintering method in which polymer particles are partially fused or solidified with a binder or the like and pores between particles are used as pores.

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

The type (raw material) of the woven or nonwoven fabric 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.) And a conventional method (for example, in the case of a nonwoven fabric, a method of forming fibers into a web and bonding them by thermocompression bonding or an adhesive, a needle punch method, etc.).

Examples of natural fibers include cotton, hemp, silk, wool, and cellulose fibers. Rayon (such as viscose rayon) can be used as the recycled fiber. Examples of the semi-synthetic fibers include cellulose ester fibers (such as cellulose acetate fibers) and cellulose ether fibers (such as methyl cellulose fibers). As synthetic fibers, polyester (polyethylene terephthalate, polybutylene terephthalate, etc.), (meth) acrylic resin (poly (meth) acrylate, polyacrylonitrile, etc.), polycarbonate, polyether, polyetherester, polyamide (nylon 6, Nylon 66
), Polyimide, polyamide imide, polyolefin (polyethylene, polypropylene, etc.), halogen-containing vinyl resin (polyvinyl chloride, polyvinylidene chloride, etc.),
Fibers obtained from thermoplastic resins such as polystyrene, copolymers or crosslinked products obtained by combining the constituent units of these resins, and mixtures thereof. Preferred fibers include cellulose ester fibers (such as cellulose acetate), polyester fibers (such as polyethylene terephthalate fiber and polybutylene terephthalate fiber), polyolefin fibers (such as polyethylene fiber and polypropylene fiber), and polyamide fibers, particularly polyester fibers.

The basis weight of the woven or nonwoven fabric is, for example, 50
g / m ² or more, preferably 100 g / m ² or more (for example,
100-1000 g / m ² ), more preferably 200
About 800 g / m ² . The average fiber diameter is, for example,
0.01-100 μm, preferably 0.1-50 μm
(Particularly 1 to 10 μm). The air permeability is 0.1 ~
About 100 cm ³ / cm ² · s, preferably 0.1 to 50
It is about cm ³ / cm ² · s.

Examples of the paper include coated paper (for example, high quality paper, Kent paper, art paper, etc.), synthetic paper, and the like.

The average pore diameter 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). If the average pore size is less than 0.005 μm, the ink absorbability may be insufficient, and if the average pore size exceeds 10 μm, the water resistance and printing quality are likely to be reduced.

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%. If the porosity is less than 40%, the surface area of the absorbing surface is small, so that the absorption capacity of the support for ink is low. If the porosity exceeds 80%, the strength of the porous support itself may be reduced.

The thickness of the porous support is usually, for example, about 20 to 200 μm, and preferably about 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.

The porous support may be at least a porous surface, and may be a laminate in which a porous layer is laminated on a base material such as paper or a plastic sheet.

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 having a solubility in 100 g of water at 20 ° C. of 0.01 to 2 g, preferably about 0.01 to 1.5 g, is attached to the porous support. By attaching this organic acid, the sharpness of the image
(Print quality) can be improved, and a good-texture image receiving body can be obtained.

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 a part or all of a carboxyl group or a 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 added to the surface of the porous support at a dry adhesion amount of 0.05 g / m ² or more (for example, 0.05 g / m ² or more).
To 1 g / m ² ), preferably 0.1 g / m ² or more (for example, 0.1 to 1 g / m ² ), more preferably 0.2 to 1 g / m ^2.
About 0.8 g / m ² may be attached.

Organic acids may be used in the form of conventional additives such as dye fixing agents, stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), binders (particularly cellulose esters, polyesters, acrylics). Water-insoluble and hydrophilic resins such as resins, polyamides, polysulfones, polyamides, and polyurethanes), colorants, antistatic agents, defoamers, coatability improvers, thickeners, lubricants, dyes, pigments, antiblocking agents, You may use together with a filler, a gelling agent, etc.

[Production Method] The recording image receiving body of the present invention is obtained by adhering an organic acid having a solubility in 100 g of water at 20 ° C. of 0.01 to 2 g to at least one surface of the porous support. Can be manufactured. For details,
Conventional methods, for example, a method of applying a coating solution containing the organic acid on a porous support and drying the coating 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 coating solution can be selected according to the type of the organic acid and the like,
There is no particular limitation. For example, alcohols (C, such as methanol, ethanol, isopropanol, butanol, etc.)
_1-4 alkyl alcohols), ketones (acetone,
Di C _1-4 alkyl ketones such as methyl ethyl ketone, etc.), esters (C _1-4 alkyl formate such as ethyl formate, etc.), ethers (1,4-dioxane,
Cyclic or chain C _4-6 ethers such as tetrahydrofuran, etc., cellosolves (C _1-4 alkyllosolves such as methyl cellosolve and ethyl cellosolve), and aromatic hydrocarbons (benzene, toluene, xylene and the like). . These solvents may be used as a mixed solvent. further,
The coating liquid may be a solvent containing water. The concentration of the coating solution was as follows: organic acid / solvent (weight ratio) = 0.1 / 99.9 to 10
/ 90 (0.1 / 99.9 to 20/80), preferably about 1/99 to 10/90. Alternatively, it may be produced by impregnating the porous support with a coating solution containing the organic acid.

[0043]

According to the present invention, it is possible to obtain a recording image receiving body which is excellent in ink absorbency and blocking resistance and excellent in texture. Further, a recording image receiving body that can greatly improve surface gloss, sharpness of a recorded image, and color reproducibility can be obtained. Furthermore, a recording image receiving body having excellent water resistance and weather resistance of a recorded image can be obtained.

[0044]

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

Unless otherwise specified, parts or percentages are based on weight. The recording receivers obtained in Examples and Comparative Examples were evaluated for ink absorption, water resistance, image resolution, and blocking resistance as follows.

[Ink Absorption] Inkjet printer (MasterJet-JC20, manufactured by Graphtec)
08) and the pigment-type aqueous inks (cyan, yellow,
Magenta) was printed solid to form a recorded image. After printing, place a copy paper for PPC on the print unit at regular intervals, and apply a load of 250 g /
After applying cm ² for 10 seconds, the copy paper was peeled off, the degree of ink set-off was visually determined, and the time until set-off was no longer observed.

[Water resistance] The same printing as in the ink absorption test was carried out on the recording receivers obtained in Examples and Comparative Examples, and after immersion in water at room temperature for 24 hours, the appearance was visually evaluated according to the following criteria. did.

：: No abnormality Δ: Slight elution of image area ×: Most of image area eluted

[Image resolution] Ink jet printer (MasterJet-JC20, manufactured by Graphtec)
08), and a yellow-based magenta line (width 100 μm) was applied to the recording receivers obtained in Examples and Comparative Examples.
After printing m), dots were observed with a microscope at a magnification of 50 times, and evaluated according to the following criteria.

◎: Little bleeding around dots. ド ッ ト: Little bleeding around dots, measured value is 120.
Exceeding μm ×: Bleeding around dots, and the boundary between adjacent yellow and magenta dots is unclear

[Blocking resistance] Two or more recording image receivers obtained in Examples and Comparative Examples were superimposed on each other.
It was stored under a load of 0 g / cm ² at 40 ° C. and 90% RH for one day, and evaluated according to the following criteria.

◎: neither matting nor blocking ○: matting is present but no blocking is performed x: blocking is performed

Example 1 A polyester cloth having a thickness of 150 μm (basis weight: 92.3 g / m 2)
² ) Apply coating solution a shown below on one side of
And dried for 5 minutes at a dry weight of phthalic acid of 2.1 g /
An image receiver of m ² was obtained. Table 1 shows the evaluation results of the image receiver.

[Coating Solution a] A coating solution was prepared by adding 2 parts of phthalic acid and 98 parts of isopropanol as a solvent.

Example 2 Polyester nonwoven fabric having a thickness of 100 μm (Hirose Paper Co., Ltd.)
Co., Ltd., “05-TH48”, a basis weight of 46.0 g / m ² ) was coated with the coating solution a on one side and dried at 80 ° C. for 5 minutes to obtain a phthalic acid dry adhesion of 1.9 g / m ^2. Was obtained. Table 1 shows the evaluation results of the image receiver.

Example 3 Ink-jet compatible PPC paper (manufactured by Kishu Paper Co., Ltd., F
C Dream) is coated with a resin solution b shown below on one side and dried at 70 ° C. for 5 minutes to form a sheet having an 8 μm thick porous plastic layer in which pores having an average pore diameter of 1 μm are present at high density. I got The coating liquid a was applied to the plastic sheet and dried at 80 ° C. for 5 minutes to obtain an image receiving body having a dry adhesion amount of phthalic acid of 0.5 g / m ² . Table 1 shows the evaluation results of the image receiver.

[Resin Solution b] Cellulose acetate (acetylation degree: 55, average polymerization degree: 170) as a cellulose derivative,
10% solution made using acetone as good solvent 1
Cyclohexanol 10 as a poor solvent
0 part was added to prepare a resin solution b.

Comparative Example 1 The coating solution a was applied to one side of a 100 μm-thick polyethylene terephthalate film (Melinex 339, manufactured by DuPont Japan), and dried at 80 ° C. for 5 minutes.
An image receiving body having a dry adhesion amount of phthalic acid of 0.5 g / m ² was obtained. Table 1 shows the evaluation results of the image receiver.

Comparative Example 2 Polyvinyl alcohol (OKS7158G, manufactured by Nippon Synthetic Chemical Co., Ltd.) of 18 was added to the polyester cloth used in Example 1.
% Aqueous solution and dried at 120 ° C for 5 minutes to a thickness of 15%.
A μm image receiving layer was provided. Table 1 shows the evaluation results of the image receiver.

[0060]

[Table 1]

In Comparative Example 1, there was no ink absorption, and no image was formed. The texture of the processed product of the example was not different from that of the unprocessed product.

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Claims (6)

[Claims] 1. The method according to claim 1, wherein at least one surface of the porous support has
The solubility in water of 100 g at 20 ° C. is 0.01 to
A recording image receiver to which 2 g of an organic acid is attached. 2. The organic acid having a dry adhesion amount of 0.05 g / m ^2.
The recording image receiving body according to claim 1, wherein: 3. The recording image receiver according to claim 1, wherein the porous support is a porous plastic sheet or cloth. 4. The recording image receiving body according to claim 1, wherein the cloth is a woven cloth or a nonwoven cloth. 5. The method according to claim 1, wherein at least one surface of the porous support comprises:
The solubility in water of 100 g at 20 ° C. is 0.01 to
A method for producing a recording image receiver to which 2 g of an organic acid is attached. 6. The method according to claim 5, wherein the organic acid is adhered by applying or impregnating a coating solution containing the organic acid.