JPH0939375A - Ink jet recording sheet and method of manufacturing the same - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To develop an ink jet recording sheet which is excellent in ink absorption and water resistance and is also excellent in transportability in a printer. SOLUTION: On the surface of a support, (A) 100 parts by weight of a water-soluble polymer (B) the weight of a poorly water-soluble monomer having 2 or more, preferably 3 or more ethylenically unsaturated groups in one molecule. An ink jet recording sheet in which layers of a polymer composition composed of 1.0 to 30 parts by weight of a combination (C) 0.5 to 20 parts by weight of silicone oil are laminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording sheet and a method for producing the same.

[0002]

2. Description of the Related Art Ink jet recording methods have recently become rapidly popular due to their low noise, high speed printing, and easy colorization. By the way, in the ink jet printer, in order to prevent the jet nozzle clogging,
It is usual to use an ink having a low drying property. Therefore, the composition of the ink is such that a binder, a dye, a solvent, an additive and the like are dissolved in water. Therefore, it is necessary to use a recording sheet having high ink absorbency. Further, the inkjet recording sheet is also required to have water resistance such that the recording layer is not peeled off even when water droplets or sweat are attached, and the recorded image does not bleed.

Against this background, Japanese Patent Laid-Open No. 6-155
No. 895, on a support, polyvinylpyrrolidone and / or acetoacetylated polyvinyl alcohol,
An inkjet recording sheet is disclosed in which a water-soluble and / or water-dispersible electron beam-curable compound and a water-based coating composition made of polyethylene glycol are applied and cured by irradiation with an electron beam.

[0004]

An ink jet recording sheet obtained by coating and curing a polymerizable composition comprising such a water-soluble polymer and a polymerizable monomer on a support has an ink absorption of a certain level or more. Excellent in water resistance and water resistance.
However, the recording sheet has a problem in sheet transportability, that is, the smoothness of feeding the sheet from setting the recording sheet in the printer to the ready-to-print state. However, it is easy to cause a problem that the printer cannot be set in a printable state unless it is manually corrected.

On the other hand, Japanese Patent Publication No. 3-24908 discloses that
An inkjet recording sheet is disclosed in which a support is coated with or impregnated with a coating liquid comprising a pigment, a water-soluble polymer binder, and a water-soluble silicone compound or a silicone emulsion. However, although this publication describes that this ink jet recording sheet is effective in improving color misregistration, as described above, the coating liquid contains a polymerizable monomer and is cured. Nothing is mentioned. Thus, the recording sheet was still satisfactory in terms of the transportability of the sheet, although it was somewhat good.

Under the circumstances, an object of the present invention is to develop an ink jet recording sheet which is excellent in ink absorbency and water resistance and is also excellent in transportability in a printer.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in light of the above circumstances. As a result, it was found that the above problem can be solved by laminating a layer of a polymer composition comprising a water-soluble polymer, a polymer of a poorly water-soluble monomer, and silicone oil on the surface of a support. Has been completed.

That is, the present invention provides (A) 100 parts by weight of a water-soluble polymer on the surface of a support (B) A polymer of a poorly water-soluble monomer having two or more ethylenically unsaturated groups in one molecule. An ink jet recording sheet having a layer of a polymer composition of 0.0 to 30 parts by weight (C) silicone oil of 0.5 to 20 parts by weight.

Further, the present invention provides (a) 100 parts by weight of a water-soluble polymer (b) 1.0 to 30 parts by weight of a poorly water-soluble monomer having two or more ethylenically unsaturated groups in one molecule (c ) Silicone oil 0.5 to 20 parts by weight (d) Radical polymerization initiator 0.0005 to 5 parts by weight dispersed in water or a polymerizable composition, and the polymerizable composition on the surface of a support. Also provided is a method for producing the above-mentioned inkjet recording sheet, which comprises coating, drying and then polymerizing.

The support used in the present invention is not particularly limited, but when it is used as a light transmissive recording medium for an overhead projector (hereinafter abbreviated as OHP), it is not transparent. An excellent and flexible plastic film is preferably used. Examples of these film materials include polyethylene terephthalate, polyvinyl chloride, polycarbonate, polypropylene and the like. Further, an opaque base material such as paper, synthetic paper and white film can be used as the support. The ink jet recording layer may be formed on both sides of these supports, but it is more advantageous to form the ink jet recording layer on one side from the viewpoint of cost.

In the present invention, as the water-soluble polymer which is a constituent of the polymer composition to be laminated on the surface of the above-mentioned support, known water-soluble polymers can be used without particular limitation. Specifically, albumin, gelatin, casein, polyvinyl alcohol,
Examples thereof include polyacrylic acid, sodium polyacrylate, polyvinylpyrrolidone, methylcellulose and hydropropylmethylcellulose, and one or more of these various water-soluble polymer substances are used. It is particularly preferable to use polyvinyl alcohol.

On the other hand, in the present invention, as the polymer of the poorly water-soluble monomer containing two or more ethylenically unsaturated groups in one molecule constituting the polymer composition, known polymers can be used without any limitation. it can. Here, the poorly water-soluble monomer has a solubility in water of 2% by weight or less at 20 ° C., preferably 1%.
It is preferable to use the one having a weight% or less. Specifically, ethylene glycol di (meth) acrylate (means acrylate and methacrylate; hereinafter the same expressions are used), diethylene glycol di (meth)
Acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( Polyester of a polyol such as (meth) acrylate and an ethylenically unsaturated carboxylic acid; a unit amount of urethane (meth) acrylate such as glycerin di (meth) acrylate isohexamethylene diisocyanate, pentaerythritol tri (meth) acrylate hexamethylene diisocyanate There is a polymer of the body. These polymers are the same as those of the above monomers.
You may use what copolymerized the kind or more.

In the present invention, the use of a polymer of a monomer which is poorly water-soluble and which contains two or more ethylenically unsaturated groups in one molecule, as a constituent of the ink jet recording layer, The absorption rate of the ink and the water resistance of the coating film can be greatly improved. In addition, from the viewpoint of the ink absorption rate and the effect of improving water resistance, the polymer of the poorly water-soluble monomer containing two or more ethylenically unsaturated groups in one molecule is ethylenic. It is preferable to contain three or more unsaturated groups.

Here, when the monomer constituting the polymer is water-soluble, it is necessary to add a large amount of the polymer in order to impart sufficient water resistance to the coating film. Causes a decrease in the ink absorption rate, making it difficult to improve both the water resistance and the ink absorption rate.

In the present invention, the above-mentioned polymer is a sparingly water-soluble polymer which contains one ethylenically unsaturated group in one molecule in addition to the above-mentioned bifunctional or higher monomer as long as the coating film properties are not impaired. A small amount of the above monomer, preferably, a copolymerized amount of 30 mol% or less may be used. Monofunctional monomers include methyl (meth) acrylate and ethyl (meth)
Examples thereof include alkyl esters of ethylenically unsaturated carboxylic acids such as acrylate.

In the present invention, the mixing ratio of the water-soluble polymer and the polymer of a poorly water-soluble monomer containing two or more ethylenically unsaturated groups in one molecule is 100 parts by weight of the former.
The latter is 1.0 to 30 parts by weight, preferably 1.0 to 13.0
Parts by weight, more preferably 2.0 to 12.0 parts by weight, are selected. If the amount is 1.0 parts by weight or less, the ink absorption rate is improved, the water resistance is not improved, or the line image does not exhibit good properties. If the amount is 30 parts by weight or more, no further improvement in the ink absorption rate can be expected. Then, it begins to decrease, and further increases the turbidity, which is not preferable.

In the present invention, silicone oil is further added to the polymer composition constituting the ink jet recording layer. This improves the transportability of the recording sheet in the printer. This effect is more remarkable when the polymer composition serving as the medium of the recording layer contains a polymer of a poorly water-soluble monomer containing two or more ethylenically unsaturated groups in the molecule. As a result, in the present invention, an inkjet recording sheet having extremely good transportability can be obtained.

Here, as the silicone oil, known ones can be used without any limitation. Preferable examples include dimethyl silicone oil, diphenyl silicone oil, methylphenyl silicone oil and the like. Further, polyether modified products, alcohol modified products, and carboxyl modified products of these silicone oils can also be used. In addition, such silicone oil is usually preferably used in a state of being dispersed in water, except for those made water-soluble by the above-mentioned modification and the like.

In the present invention, one or more kinds of the above silicone oils are used, and the compounding amount thereof is 0.5 to 20 parts by weight, preferably 1.
It is 0 to 18 parts by weight. If it is 0.5 parts by weight or less, no improvement in transportability is observed, and if it is 20 parts by weight or more, further improvement in transportability cannot be expected, and if it is excessively compounded, haze and water resistance are decreased, which is not preferable. .

The ink jet recording sheet of the present invention comprises
It may be manufactured by any method. Preferably, (a) 100 parts by weight of a water-soluble polymer, (b) 1.0 to 30 parts by weight of a poorly water-soluble monomer having two or more ethylenically unsaturated groups in one molecule on the surface of the support (c) ) Silicone oil 0.5 to 20 parts by weight (d) Radical polymerization initiator 0.0005 to 5 parts by weight and a polymerizable composition dispersed or dissolved in water are applied, dried, and then polymerized. Preferably.

The amount of water used to disperse or dissolve the above components is not particularly limited, but is usually 700 to 100 parts by weight of the water-soluble polymer.
It is common to use 1700 parts by weight. In preparing the polymerizable composition, an aqueous dispersion or aqueous solution of (b) a poorly water-soluble monomer or (d) a radical polymerization initiator is first prepared, and an aqueous solution of the water-soluble polymer and Is preferably performed by mixing silicone oil. When the poorly water-soluble monomer (b) is mixed with water, a water-soluble polymer or a surfactant may be used as an emulsifier.

The radical polymerization initiator is not particularly limited, but examples thereof include benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether; diethoxyacetophenone, 4-phenoxydichloroacetophenone and the like. Acetophenones; thioxanthones such as thioxysanson and 2-chlorothioxanthone are used. In order to properly polymerize the poorly water-soluble monomer (b), the blending amount thereof is based on 100 parts by weight of the water-soluble polymer.
It is necessary that the amount is 0.0005 to 5 parts by weight, preferably 0.005 to 3 parts by weight.

In the polymerizable composition, in addition to the above components, a film-forming aid, a plasticizer, an antifoaming agent, a surfactant, an antifungal agent, an antiseptic agent, a thickener, an aqueous emulsion, and a pH adjusting agent. Agent,
Additives such as organic solvents, or to prevent stickiness and blocking properties of the recording layer surface, or various fillers to the extent that transparency is not hindered for the purpose of adjusting ink bleeding, for example, silica, colloidal silica, clay, Talc, diatomaceous earth,
Fillers such as calcium carbonate, calcium sulfate, aluminum silicate, synthetic zeolite, alumina and zinc oxide can be dispersed. Further, a fluorine-based surfactant may be added for the purpose of eliminating the gaps between the dots by appropriately spreading the ink dots and improving the sharpness of the image.

The method of applying the polymerizable composition onto the surface of the support may be any method, but preferably, the aqueous dispersion is applied onto the surface of the support by roll coating, bar coating, gravure coating or air knife coating. And the like, and dried. The coating amount is usually 1 to 20 in terms of solid content in consideration of the speed of absorption of ink, economy, uniformity of a film to be formed, and the like.
g / m ^2, preferably suitably 3 to 10 g / m ^2.

The polymerization may be carried out by thermal polymerization or the like, but it is generally preferable to carry out irradiation. An electron beam or an ultraviolet ray is usually used as the radiation. Ultraviolet rays are obtained with a mercury lamp, a xenon lamp, a metal halide lamp, etc., and an electron beam is obtained with an electron beam accelerator. In addition, when polymerizing using an electron beam, it is possible to polymerize even if it does not mix a radical polymerization initiator.

The ink jet recording sheet thus obtained is excellent in the transparency of the ink jet recording layer. Therefore, when a highly transparent support is used, the haze measured according to JIS-K6714 is 2 or less.
A value of 0% or less is obtained. Those having such a degree of haze are superior in sharpness of an image when projected on an OHP.

[0027]

The ink jet recording sheet of the present invention has fast ink absorption and good water resistance. Further, there is an advantage that the recording sheet is easily transported in the printer. Also, the haze of the ink jet recording layer is low.

The ink jet recording sheet of the present invention comprises
It can be suitably used as a color printing type ink jet recording sheet. It is also suitable for optical recording media such as OHP.

[0029]

EXAMPLES Examples will be given below for specifically explaining the present invention, but the present invention is not limited to these examples. In the following examples and comparative examples, the properties of the ink jet recording sheets obtained were evaluated by the following methods.

(1) Haze Using a color difference meter (Σ80 manufactured by Nippon Denshoku Industries Co., Ltd.), JISK
It was measured according to -6714.

(2) Ink absorption speed When solid printing is performed in blue on a color printing type ink jet printer (MJ-700V2C manufactured by Seiko Epson Corp.), printing on a recording material is touched at regular intervals. The time when the ink dries and does not adhere to the finger was measured.

(3) Water resistance A water drop was dropped on the surface of the ink jet recording layer and rubbed with a finger to determine whether or not the layer was peeled off.

○ ---- No peeling at all △ ---- Slightly peeling off the layer X ---- Peeling off the layer (4) Conveyability A recording sheet was printed with an ink jet printer (MJ-700V2C manufactured by Seiko Epson Corporation). Then, it is determined whether or not the sheet is smoothly fed and printing is possible.

○ ---- Printing is possible without requiring manual correction. △ ---- Printing is possible with slight manual correction. Printable state by modification Example 1 0.08 parts by weight of sodium lauryl sulfate and polyvinyl alcohol (Nippon Gosei Kagaku KK, Gohsenol G)
H-17) 1.4 parts by weight is dissolved in 45.3 parts by weight of water,
After the temperature of this aqueous solution was raised to 70 ° C., a mixture of the following composition pentaerythritol triacrylate 22.8 parts by weight photopolymerization initiator 0.9 parts by weight (Merck Japan KK-made Darocur 1173) was continuously stirred, An aqueous dispersion was obtained.

The above-obtained aqueous dispersion, 2,820 parts by weight of a 10% by weight aqueous solution of polyvinyl alcohol (Nippon Gosei Kagaku KK, Gohsenol KH-17) aqueous solution, and
11.28 water-soluble polyether-modified silicone oil (KF615 (A), manufactured by Shin-Etsu Silicone Co., Ltd.)
The polymerizable composition was prepared by mixing with a part by weight. A 100 μm thick polyethylene terephthalate film (manufactured by Dia foil Co., Ltd., O-300) was obtained.
E) was applied with a bar coater so that the film thickness after drying was 7 μm, and dried with warm air at 60 ° C., then a UV irradiation device manufactured by Toshiba Corp. (high pressure mercury lamp, 80 W / cm 2 lamp, Irradiation was performed once using a conveyor speed of 3 m / min) to polymerize the composition.

The obtained ink jet recording sheet is
The properties of the recording layer were evaluated by printing with the inkjet printer, and the results are shown in Table 2.

Example 2 In Example 1, the addition amount of KF615 (A) was 2.8.
In the same manner as in Example 1 except that the amount was changed to 2 parts by weight,
The polymerizable composition was adjusted to obtain an inkjet recording sheet. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Example 3 In Example 1, the addition amount of KF615 (A) was 45.
The polymerizable composition was adjusted in the same manner as in Example 1 except that the amount was changed to 12 parts by weight to obtain an inkjet recording sheet. The recording layer was evaluated in the same manner as in Example 1 and Table 2
The results are shown in.

Example 4 Example 4 was repeated except that the total amount of KF615 (A) was changed to an aqueous dispersion of polydimethylsiloxane (SH-7028 manufactured by Toray Silicone Co., Ltd., 30% by weight of active ingredient). In the same manner as in 1, prepare the polymerizable composition,
An inkjet recording sheet was obtained. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Example 5 All the same as Example 1 except that the 10 wt% polyvinyl alcohol aqueous solution was changed to 7,600 parts by weight and the addition amount of KF615 (A) was changed to 30.4 parts by weight. Then, the polymerizable composition was adjusted to obtain an ink jet recording sheet. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2 and the results are shown.

Example 6 The same as Example 1 except that the 10% by weight aqueous polyvinyl alcohol solution was changed to 2,072 parts by weight and the addition amount of KF615 (A) was changed to 8.29 parts by weight. Then, the aqueous dispersion was prepared to obtain an ink jet recording sheet. The recording layer was evaluated in the same manner as in Example 1,
The results are shown in Table 2 and the results are shown.

Example 7 An ink jet recording sheet was prepared by preparing a polymerizable composition in the same manner as in Example 1 except that the total amount of pentaerythritol triacrylate was changed to diethylene glycol dimethacrylate. . The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2 and the results are shown.

Example 8 In Example 1, 3,820 parts by weight of 2,820 parts by weight of 10% by weight polyvinyl alcohol aqueous solution were added to 3,525 parts by weight of 8% by weight of hydroxypropylmethylcellulose (Metronose 65SH50 manufactured by Shin-Etsu Chemical Co., Ltd.). A polymerizable composition was prepared in the same manner as in Example 1 except that the composition was changed.
An inkjet recording sheet was obtained. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2 and the results are shown.

Comparative Example 1 An ink jet recording sheet was obtained by adjusting the polymerizable composition in the same manner as in Example 1 except that KF615 (A) was not added. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 2 In Example 1, the addition amount of KF615 (A) was adjusted to 0.
The polymerizable composition was prepared in the same manner as in Example 1 except that the amount was changed to 56 parts by weight to obtain an inkjet recording sheet. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 3 In Example 1, the addition amount of KF615 (A) was set to 67.
The polymerizable composition was prepared in the same manner as in Example 1 except that the amount was changed to 68 parts by weight to obtain an inkjet recording sheet. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Comparative Example 4 An aqueous solution was prepared in the same manner as in Example 1 except that the aqueous dispersion of pentaerythritol triacrylate was not added in Example 1 to obtain an ink jet recording sheet. The recording layer was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[0048]

[Table 1]

[0049]

[Table 2]

Claims (3)

[Claims] 1. A polymer (A) 100 parts by weight of a water-soluble polymer (B) a polymer of a poorly water-soluble monomer having 2 or more ethylenically unsaturated groups in one molecule 1.0 to 30. Parts by weight (C) Silicone oil 0.5 to 20 parts by weight An inkjet recording sheet comprising a layer of a polymer composition. 2. (a) 100 parts by weight of water-soluble polymer (b) 1.0 to 30 parts by weight of poorly water-soluble monomer having two or more ethylenically unsaturated groups in one molecule (c) Silicone oil 0 0.5 to 20 parts by weight (d) Radical polymerization initiator 0.0005 to 5 parts by weight and a polymerizable composition dispersed or dissolved in water. 3. The method for producing an ink jet recording sheet according to claim 1, wherein the surface of the support is coated with the polymerizable composition according to claim 2, dried and then polymerized.