JPH09174997A - Ink jet recording sheet and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to obtain the excellent glossiness without necessity of after treatment for giving gloss by providing an ink receiving layer on the smooth surface of a sheet-like support, providing an intermediate layer on the opposite surface, and transferring the receiving layer onto the intermediate layer. SOLUTION: The first surface of a sheet-like support drawn from an unreel is coated with an ink receiving layer by a coating unit 1. In a No. 1 dryer 2, the receiving layer is dried. Then, the second surface is coated with an intermediate layer of adhesive by a coating unit 3. When a sheet is wound on a reel, the receiving layer and the intermediate layer are press bonded by using a nip roller 5. When the manufactured roll is drawn, the receiving layer is transferred toward the intermediate layer. Thus, an ink jet recording sheet having excellent ink absorption properties and high glossiness can be manufactured without liner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet recording sheet for recording using an aqueous ink, and more particularly to an inkjet recording sheet which can be linerless and can be manufactured at low cost, and a manufacturing method thereof.

[0002]

2. Description of the Related Art The ink jet recording system is one in which minute droplets of ink are ejected according to various operating principles and adhered to a recording sheet such as paper to record images, characters, etc., but at high speed and low noise. , Easy to multicolor, great flexibility of recording pattern, no need for development and fixing,
It is rapidly spreading in various uses as a recording device for various figures and color images including kanji. Furthermore, images formed by the multi-color inkjet method can obtain records that are comparable to those of multi-color printing by the plate-making method and printing by the color photographic method. Since it is cheaper than the technology, it is being widely applied to the field of full-color image recording.

A recording sheet used in this ink jet recording system has a high density of print dots and a vivid color tone, and ink flows out even when print dots overlap due to quick ink absorption. It is required that the ink does not bleed, that the diffusion of the print dots in the lateral direction is not excessively large, and that the periphery is smooth and does not blur. Several proposals have been made in the past to solve these problems. For example, JP-A-52-5
Japanese Patent No. 3012 discloses an inkjet recording paper obtained by wetting a low-sized base paper with a coating material for surface processing. Further, JP-A-55-5830 discloses an ink jet recording paper having an ink-absorbent coating layer on the surface of a support, and JP-A-55-51583 and JP-A-56-157. Japanese Patent Laid-Open Publication No. Sho 5/1982 discloses an example of using non-colloidal silica powder as a pigment in a coating layer.
Japanese Patent Laid-Open No. 5-11829 discloses that two ink absorption speeds are different.
An example of coated paper using a layered structure is disclosed.

However, in general, the ink receiving layer having ink absorbability must have many voids for absorbing and holding ink. Therefore, of course, the ink receiving layer with many voids has a lot of micro unevenness on the interface with the air and on the surface of the coating layer, so that the incident light to the ink receiving layer is scattered or the transmission is hindered, resulting in a gloss. It is hard to come out and becomes opaque. Furthermore, since it becomes difficult for light to reach the ink that has penetrated into the voids, the image becomes whitish, and the color reproducibility and color density deteriorate. Several proposals have been made in the past in order to solve such defects and obtain a glossy feeling.

For example, as a post-treatment method, JP-A-53-3 is used.
Nos. 5538 and 53-35539 disclose methods of ejecting a gloss liquid after printing.
50744, 59-196285, 59-2018.
91, 59-204591, 59-204592, 59-222381 and the like, after printing on a recording sheet containing a thermoplastic resin and its fine particles,
A method of performing treatment using heat, pressure, a plasticizer or an organic solvent is disclosed, and JP-A-57-63264 discloses a method of applying a transparent toner after printing and performing a pressure treatment.
Japanese Patent Laid-Open No. 56-77154 discloses a method of filling voids after printing with a non-volatile colorless substance. Further, JP-A-59-190885 discloses a method of impregnating and curing a photo-curable resin after printing.
Japanese Patent No. 50370 discloses a method of performing heat treatment after printing on a recording paper containing synthetic pulp. However, the above-mentioned post-processing method is not practical because it requires an apparatus for post-processing that can obtain a glossy recorded image and the operation becomes complicated. Therefore, there is a demand for an inkjet recording sheet which does not require post-treatment for imparting such gloss and has an excellent gloss on the recording surface and the image recording portion, and which has high ink absorbency.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides an ink jet recording sheet having excellent glossiness without the need for post-treatment for imparting gloss and a method for producing the same. To do.

[0007]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted various studies on a method for producing an ink jet recording sheet, and as a result, have found that the smooth first surface (preferably the center line surface roughness of the sheet-shaped support has 1 μm or less) is provided with an ink receiving layer,
When the intermediate layer is applied to the second surface and rolled into a roll, the ink receiving layer moves to the intermediate layer (an adhesive layer can be exemplified) side, and an inkjet recording sheet with high glossiness can be manufactured. I found a thing.

The present invention includes the following aspects. [1] A smooth surface (first surface) having a smooth surface having peelability (first surface) and an opposite surface (second surface)
Surface) and an ink receiving layer provided on the second surface and an intermediate layer having adhesiveness or tackiness provided on the second surface, and the sheet is wound to bond the ink receiving layer and the intermediate layer together to form the ink receiving layer. An inkjet recording sheet formed by transferring onto an intermediate layer.

[2] A smooth surface having peelability (first
Surface) and an opposite surface (second surface) of the sheet-like support, a smooth surface (first surface) is provided with an ink receiving layer, and a second surface is provided with an adhesive or tacky intermediate layer, Next, a method for producing an inkjet recording sheet, in which the obtained ink-receiving layer and the intermediate layer are bonded to each other by winding the obtained sheet to transfer the ink-receiving layer onto the intermediate layer.

[3] The smooth surface of the sheet-like support (first
The method for producing an inkjet recording sheet according to [2], wherein the center line surface roughness of the surface) is 1 μm or less. [4] Production of the inkjet recording sheet according to [2] or [3], wherein the intermediate layer contains at least one selected from the group consisting of an adhesive, a pressure-sensitive adhesive, and a thermoplastic resin in a heat-melted state. Method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A method for manufacturing an ink jet recording sheet of the present invention will be described with reference to FIG. First, the ink receiving layer is applied to the first surface of the sheet-shaped support pulled out from the unreel by the coating device (1). The center line average roughness of the first surface is preferably 1 μm or less. This makes it possible to obtain an ink receiving layer that is smooth and has excellent gloss. After that, No. In one dryer (2)
The ink receiving layer is dried. Next, the coating device on the second surface
Apply (3) an intermediate layer such as an adhesive. No. if necessary. 2 Dry in the dryer (4).

The structure of the seat at this point is shown in FIG. Next, take up this sheet with a reel.
At this time, the ink receiving layer and the intermediate layer such as the adhesive layer are pressure bonded using the nip roll (5).

When the roll manufactured in this manner is pulled out, the ink receiving layer is transferred to the intermediate layer such as the adhesive layer,
An inkjet recording sheet having a glossy feeling can be obtained. A cross-sectional view of the ink jet recording sheet manufactured in this way is shown in FIG. When manufactured in this way, it is not necessary to prepare a molding surface for finishing the ink receiving layer into a smooth surface separately from the support, and the manufacturing process can be simplified. In other words, it is possible to make a linerless and to manufacture at low cost.

The sheet-like support used in the present invention has a smooth surface (first surface) on which the ink-receiving layer is coated, and has some peelability. As such a sheet-like support, metal foil, synthetic paper, polymer film, polymer resin laminated paper, or the like can be used. Examples of the polymer material include polyesters such as polyethylene terephthalate, cellulose esters such as nitrocellulose, cellophane, cellulose diacetate, cellulose triacetate and cellulose acetate butyrate.
Furthermore, polysulfone, polyphenylene oxide, polyimide, polycarbonate, polyamide, acrylic resin, polyvinyl chloride and the like can be mentioned. The thickness of the sheet-shaped support is not particularly limited, but is 10 to 300 μm.
Those which are easy to handle are preferable. The surface (first surface) of the sheet-shaped support on which the ink receiving layer is coated is preferably smooth, and the center line surface roughness Ra (JIS B 0601) is 1 μm.
m or less is preferable, and 0.5 μm or less is more preferable. Although there is no particular lower limit, a smooth one up to about 0.001 μm is currently available.

As the first surface of such a support, the above-mentioned one can be used without treatment. However, in order to improve the releasability between the first surface and the ink receiving layer, it is effective to coat the releasable resin such as silicone or fluororesin on the first surface of the support. The releasability can be further improved by coating the first surface with a releasable resin. The coating amount is preferably about 0.05 to 3 g / m ² . The first surface may be subjected to hydrophilic treatment by corona discharge or plasma treatment.

As the substance used in the ink receiving layer of the present invention, known pigment fine particles and water-soluble resin can be used. The pigment fine particles used in the ink receiving layer in the present invention include montmorillonite group minerals, hydrotalcite group minerals, zeolite, synthetic fine particle silica, calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium oxide, and oxide. Zinc, zinc carbonate, aluminum silicate, aluminum hydroxide, aluminum oxide, calcium silicate, magnesium silicate, polyaluminum hydroxide compound, alumina hydrate, colloidal silica, grain starch particles, modified starch particles, plastic pigments, urea resin pigments Inorganic or organic pigments or particles such as crystallized cellulose particles and non-crystallized cellulose particles can be exemplified. These pigment fine particles may be untreated, may be inorganic treated with alumina, silica, titanic acid, etc., silane coupling, polyalcohol, organic treatment with polysiloxane, etc., cationized, anionized, nonionized, betaine. Chemical treatment may be applied. For montmorillonite group minerals, hydrotalcite group minerals, etc., cationization,
Anionization, nonionization or betaineization treatment may be performed.

Examples of binders include casein, gelatin, starch-based polysaccharides (dextrin, soluble starch, pregelatinized starch, brillan, etc.) and their derivatives and cellulose derivatives [nitrocellulose, carboxymethylcellulose (CMC), methylcellulose (MC), hydroxy. Propyl methyl cellulose (HPMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC)
Etc.], water-soluble resins such as completely saponified or partially saponified polyvinyl alcohol, polyethylene oxide, polypropylene oxide, and ethylene oxide / alkylene oxide copolymers.

The ink receiving layer may contain a surfactant. Examples of the surfactant include various anionic, cationic, betaine and nonionic surfactants. For example, nonionic surfactants such as saponin-based alkylene oxide derivatives, glucidol derivatives, alkyl esters such as fatty acid esters of polyhydric alcohols; alkyl carboxylates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfates , Alkyl phosphates, N-
Acyl-N-alkyl taurine acid, sulfosuccinic acid ester, sulfoalkyl polyoxyethylene alkylphenyl ethers, carboxy groups such as polyoxyethylene alkyl einic acid esters, sulfo group, phospho group, sulfuric acid ester group, phosphoric acid ester group, etc. Anionic surfactant containing an acidic group of

Amphoteric surfactants such as amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphoric acid esters, alkylbetaines, aminooxides; alkylamine salts, aliphatic or aromatic quaternary ammonium salts, pyridinium, Mention may be made of heterocyclic quaternary ammonium salts such as imidazolium and cationic surfactants such as phosphonium or sulfonium salts containing aliphatic or heterocyclic rings. Fluorine-based surfactants are also anionic, cationic, nonionic,
The betaine type can be mentioned.

Further, at the time of forming the ink receiving layer, various known additives such as a dispersant, a fluorescent dye, a pH adjusting agent, a defoaming agent, a lubricant, an anti-fading agent and an antiseptic agent may be used, if necessary. Is also good.

Examples of the intermediate layer provided on the second surface (back side of the first surface) of the support include the following adhesives. Thermoplastic resin (ethyl cellulose, vinyl acetate resin and its derivatives, polyethylene, ethylene vinyl acetate copolymer, polyvinyl alcohol, acrylic resin, polystyrene and its copolymer, polyisobutylene, hydrocarbon resin, polypropylene, polyamide resin, polyester resin, etc. Various publicly known thermoplastic resins); adhesives (thermosetting resins such as urea resin, phenol resin, epoxy resin, polyisocyanate resin, polyvinyl acetal / phenol resin, rubber / phenol resin, epoxy / nylon resin, etc. composites Various publicly known adhesives such as polymer adhesives, rubber-based adhesives such as latex-type rubber bases, hydrophilic natural polymer adhesives such as starch, glue, and casein; pressure-sensitive adhesives (solvent-type pressure-sensitive adhesives) Agent, emulsion type pressure sensitive adhesive, hot melt type feeling Adhesives, various known and used pressure-sensitive adhesives such as a delayed type pressure sensitive adhesive) is used Tekisen. The coating amount is not limited 2.0g / m ² ~50g / m ² approximately. The thermoplastic resin can be used in a state where it is provided with adhesive properties by melt coating (referred to as a heat-melted state).

The ink receiving layer coating material of the present invention is applied by a known coating machine such as a bar coater, a roll coater, an air knife coater or a gravure coater. Although not particularly limited, the coating amount of the ink receiving layer is 0.5 to 5
0.0 g / m ² is preferable, and 1.0 to 4 is more preferable.
It is 0.0 g / m ² . Even if the coating amount is large, the effect is saturated and the need is poor. Also, if the coating amount is small,
There is a risk that ink absorption will be insufficient and bleeding will occur. The intermediate layer-coated surface (second surface) of the sheet-shaped support is pre-treated, if necessary, with anchor coat treatment, corona discharge treatment, radiation treatment, plasma treatment or the like to improve the wettability of the coated surface. Or, the adhesion with the intermediate layer can be improved. As the coating device, one exemplified as the coating means for the ink receiving layer can be appropriately selected.

[0023]

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

Example 1 Manufactured according to FIG. Commercially available PET film (manufactured by Panak Co., Ltd., trademark: Lumirror X-20, thickness: 250 μm)
m, the center line surface roughness Ra of the first surface Ra = 0.02 μm) is used as a sheet-like support, and the ink receiving layer coating material 1 is applied and dried on the first surface so that the applied amount after drying is 15 g / m ^2. To form an ink receiving layer. Next, the intermediate layer paint 1
Apply to the surface so that the coating amount after drying is 10 g / m ² and dry to form an adhesive layer, and wind it into a roll while pressing the winding roll (20 kg / cm) with the nip roll (5). I took it. Next, when the sheet was pulled out from this roll and rewound, the ink receiving layer was transferred onto the intermediate layer, and an inkjet recording sheet having a cross-sectional view shown in FIG. 3 was obtained.

Ink Receptive Layer Paint 1 Polyvinyl alcohol (Kuraray Co., Ltd., trademark: R-1
130) 10 parts by weight, 90 parts by weight of water Intermediate layer paint 1 Polyester adhesive (made by Toyo Morton, trademark: AD
-578A) 10 parts, polyisocyanate crosslinking agent (trade name: CAT-50, manufactured by Toyo Morton Co., Ltd.) 14 parts, 10% ethyl acetate solution 76 parts

Example 2 Instead of the ink receiving layer coating material 1, the above ink receiving layer coating material 2 was used.
An inkjet recording sheet was obtained in the same manner as in Example 1 except that was used. Ink receiving layer paint 2 100 parts by weight of colloidal silica (Nissan Chemical Co., Ltd., trademark: Snowtex 20L), 10 parts by weight of polyvinyl alcohol (Kuraray Co., Ltd., trademark: R117), 90 parts by weight of water

Example 3 Instead of the ink receiving layer coating material 1, the ink receiving layer coating material 2 was used.
And an intermediate layer coating material 2 was used in place of the intermediate layer coating material 1, and an ink jet recording sheet was obtained in the same manner as in Example 1. Intermediate layer paint 2 100 parts of acrylic emulsion type pressure sensitive adhesive (trade name: L-145A manufactured by Nippon Carbide Industries Co., Ltd.)

Comparative Example 1 A commercially available PET film (trademark: Lumirror X-20, thickness: 250 μm, manufactured by Panac Co., Ltd.) was used as a sheet-like support, and the ink receiving layer coating material 1 was dried on the first surface. An ink-receiving layer was formed by coating and drying so that the coating amount was 15 g / m ² to obtain an inkjet recording sheet.

[Evaluation] Glossiness of the inkjet recording sheets obtained in Examples 1 to 3 and Comparative Example 1 and a commercially available inkjet printer (trade name BJC-, manufactured by Canon Inc.).
The glossiness and ink absorbency of the solid portion when recording was performed at 600 J) were evaluated by the following methods. (1) Glossiness JIS-Z-for the solid part and the blank part printed with each ink of black, yellow, magenta, and cyan.
Glossmeter (made by Nippon Denshoku Industries Co., Ltd., VG
It measured by -10) and averaged the measured value of 5 times. When the measured value is 75 or more, the glossiness is excellent.

(2) Ink absorbency The ink absorbency was evaluated by measuring the number of seconds until the printed ink dries, and rating it in three levels (◯: 5 seconds or less,
Δ: 5 to 10 seconds, ×: 10 seconds or more). When the number of seconds until the ink dries is 5 seconds or less, the ink absorbability is excellent.

[0031]

[Table 1]

The results are shown in Table 1.
Nos. 3 to 3 had good ink absorbency, and the glossiness hardly changed before and after printing. Further, from Examples 1 to 3, excellent photographic-like recorded images were obtained. For it,
In Comparative Example 1, the glossiness before and after receiving the ink was low and a photographic recording image could not be obtained.

[0033]

INDUSTRIAL APPLICABILITY The present invention is a method for producing an ink jet recording sheet having good ink absorbency and gloss. INDUSTRIAL APPLICABILITY The method for producing an inkjet recording sheet of the present invention is extremely useful in practice because it can produce an inkjet recording sheet having good ink absorbency and high gloss without a liner. Specifically, JIS-Z-871
It was a production method capable of producing an inkjet recording sheet having a 60-degree gloss of 75% or more as defined in No. 4 without a liner.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one example of a production method of the present invention.

FIG. 2 is a sectional view of the inkjet recording sheet immediately after the formation of an adhesive layer (an example of an intermediate layer) (the present invention).

FIG. 3 is a cross-sectional view of a completed inkjet recording sheet.

[Explanation of symbols]

1: Coating device, 2: No. 1 dryer, 3: coating device, 4: second dryer, 5: nip roll

Claims (4)

[Claims] 1. An ink receiving layer is provided on a smooth surface (first surface) of a sheet-shaped support having a smooth surface (first surface) having peelability and an opposite surface (second surface), and a second surface. A sheet obtained by providing an intermediate layer having adhesiveness or tackiness on the surface,
An ink jet recording sheet obtained by laminating the ink receiving layer and the intermediate layer together by winding and transferring the ink receiving layer onto the intermediate layer. 2. An ink receiving layer is provided on a smooth surface (first surface) of a sheet-like support having a smooth surface (first surface) having peelability and an opposite surface (second surface), and a second surface. Inkjet recording in which an intermediate layer having adhesiveness or tackiness is provided on the surface, and the obtained sheet is then wound to bond the ink receiving layer and the intermediate layer to transfer the ink receiving layer onto the intermediate layer. Sheet manufacturing method. 3. The method for producing an inkjet recording sheet according to claim 2, wherein the center line surface roughness of the smooth surface (first surface) of the sheet-shaped support is 1 μm or less. 4. The inkjet recording sheet according to claim 2, wherein the intermediate layer contains at least one selected from the group consisting of an adhesive, a pressure-sensitive adhesive, and a thermoplastic resin in a heat-melted state. Manufacturing method.