JP4566467B2 - Inkjet recording sheet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording sheet.
More specifically, when forming a full-color image at high density, even if a large amount of ink per unit area adheres, ink absorption, blocking resistance, beading resistance, and excellent long-term storage stability at high temperatures and high humidity The present invention also relates to an ink jet recording sheet that can provide high transmittance as required.
[0002]
[Prior art]
The ink jet recording method is attracting attention as a recording method which generates less noise and can perform high-speed printing and multicolor printing. As a recording material used in this ink jet recording method, conventionally, a recording material called a normal paper or an ink jet recording paper, which is provided with a porous ink receiving layer on a base material, transparency for OHP is used. Recording materials have been used.
[0003]
In recent years, as recording speed increases, the number of colors increases, and the performance of an ink jet recording apparatus improves, more advanced and wide-ranging characteristics are being demanded for recording materials.
[0004]
That is, as a transmissive recording material for inkjet for obtaining a high-resolution, high-quality recorded image,
1) Acceptance of ink to the recording material as quickly as possible;
2) Even if the ink dots overlap, the ink adhered later does not flow into the dots,
3) The ink droplets diffuse on the recording material and the ink dot diameter does not become larger than necessary.
4) The shape of the ink dot is close to a perfect circle, and its circumference is smooth,
5) No beading occurs (beading is a phenomenon in which a large amount of ink is unevenly distributed on the surface of the receiving layer to generate so-called “density unevenness”).
It is necessary to satisfy the basic requirements such as In particular, the beading phenomenon is prominently observed when a droplet with a large ink receiving amount is used, when the droplet discharge frequency is high, or when multicolor droplets are used as in color recording. In some cases, it becomes difficult to obtain a highly precise image.
[0005]
Inkjet recording sheets are used for projecting recorded images onto a screen or the like with an optical device such as a slide or an OHP (overhead projector), and for producing color printing positive plates. CMF (color mosaic filter) used for displays such as color separation plates and liquid crystals.
When an inkjet recording sheet is used for surface observation, the diffused light of the recorded image is a problem.
[0006]
[Problems to be solved by the invention]
The ink-receiving layer formed mainly of polyvinyl alcohol has a non-uniformity in the solid print portion because the water absorption of the resin of the ink-receiving layer is lowered in printing in a low temperature environment or storage in a high temperature and high humidity environment. There is a problem that boundary blurring occurs and a satisfactory image cannot be obtained.
[0007]
Further, the ink receiving layer formed mainly of polyvinyl pyrrolidone has a problem in that the wetness at the time of water absorption is low, so that the printer roller is easily marked or scratched during printing.
[0008]
Accordingly, an object of the present invention is to provide an ink jet recording sheet excellent in ink absorbability, blocking resistance and beading resistance even when a large amount of ink is applied at high density.
[0009]
Another object of the present invention is to provide an ink jet recording sheet excellent in long-term storage of printed matter or storage stability under high temperature and high humidity.
[0010]
[Means for Solving the Problems]
The inkjet recording sheet according to the present invention is an inkjet recording sheet having a single ink receiving layer containing a water-soluble polymer and a compound having a cationic group on the surface of a transparent film support. polymer ratio of polyvinyl alcohol and polyvinyl pyrrolidone having a saponification degree 75 to 90% is 50: 50-25: 75 a mixture of mixing ratio of the compound having the cationic group wherein the water-soluble polymer 10.0 weight 0.5 to 1.0 parts by mass with respect to parts, and the ink receiving layer contains a surfactant.
[0011]
The surfactant in claim 1 is an ink jet recording sheet which is a fluorosurfactant.
[0012]
The inkjet recording sheet of the present invention is generally composed of a base material as a support and a recording surface provided on the surface thereof, that is, an ink receiving layer.
(1) A mode in which both the base material and the ink receiving layer are translucent, and the translucent recording sheet as a whole. (2) A mode in which the surface of the ink receiving layer is smooth and glossy.
In addition, each of the ink receiving layers may have a function as a support at the same time.
[0013]
As the polyvinyl alcohol, those having a polymerization degree of 1000 or more, preferably in the range of 1000 to 3000 are used. This polyvinyl alcohol is obtained by saponifying polyvinyl acetate, and in this case, a preferable degree of saponification is 75 to 90%.
[0014]
When the degree of polymerization is less than 1000, the ink drying property (ink absorbability) of the film is deteriorated and the water resistance is also inferior. If the degree of saponification is too high, the ink drying property of the coating will be poor. Polyvinyl pyrrolidone having a molecular weight of 20000 or more, preferably in the range of 36000 to 40000 is used. When the molecular weight of polyvinyl pyrrolidone is less than 20000, the ink becomes drier and water resistant.
[0015]
The ink receiving layer of the ink jet recording sheet according to the invention contains a compound having one or more kinds of cationic groups.
The compound having a cationic group in the ink jet recording sheet according to the present invention refers to a compound that dissociates and exhibits cationic properties when dissolved in water, and typical cationic groups include primary, secondary, and tertiary amino acids. Groups and quaternary ammonium salts. Any cationic polymer can be used, and the type of the cationic polymer is not particularly limited. Examples of the cationic polymer preferably used in the present invention include the following.
[0016]
a) polyalkylene amide obtained by dehydration condensation of polyalkylene polyamine and dibasic carboxylic acid b) polyalkylene polyurea obtained by deammonia condensation of polyalkylene polyamine and urea c) polyamide obtained by deammonia condensation of polyalkylene polyamine and urea Polyurea d) Polyaminoepoxyurea obtained by reacting an amino group-containing compound with epihalohydrin e) Reaction product obtained by reacting any of the polymers a) to d) with an aldehyde f) Polymers of a) to d) above Reaction product obtained by reacting any of these with an alkylating agent g) Ring-opening polymer of ethyleneimine
h) Polymer obtained by polymerizing cationic vinyl monomer alone or copolymerized with other polymer i) Hydrolyzate of homopolymerized N-vinylamide monomer or copolymer with other copolymerizable monomer j 1) A Mannich reaction product obtained by reacting ammonia, a primary amine, or a secondary amine with formaldehyde in a polymer having active hydrogen k) A reaction product of a polymer having active hydrogen and a cationizing agent l) Ammonia in a polymer having active hydrogen Or a product obtained by reacting amines with epihalohydrin m) chitosan obtained by hydrolyzing chitin n) a polymer having active hydrogen and any of the polymers a) to m) above, and a crosslinking agent such as aldehyde, epihalohydrin, polyisocyanate, etc. Block copolymer reacted with
It is preferable to add a surfactant to the ink receiving layer of the present invention within a range that does not impair the ink absorptivity for the purpose of improving the image quality. The surfactant to be used may be any of anionic, cationic, nonionic, and betaine types, and may be a low molecular weight type, a high molecular type, or different types. Of these, fluorine surfactants are preferred.
[0019]
Fluorosurfactants include ethylene tetrafluoride, perfluoroalkyl ammonium salt, perfluoroalkyl sulfonic acid amide, sodium perfluoroalkyl sulfonate, perfluoroalkyl potassium salt, perfluoroalkyl carboxylate, perfluoroalkyl sulfone. Examples thereof include acid salts, perfluoroalkylaminosulfonates, perfluoroalkyl phosphates, perfluoroalkyl compounds, perfluoroalkyl betaines, and perfluoroalkyl halogen compounds.
[0020]
The content of the fluorosurfactant is preferably 0.01 to 6%, more preferably 0.2 to 3%. As the substrate used as a support for the ink receiving layer in the present invention, any known transparent substrate can be used. Examples of preferable transparent substrates include polyester resins, diacetate resins, and triacetates. Examples thereof include films such as resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin, polyimide resin, cellophane, and celluloid.
[0022]
Various inorganic and organic pigments such as silica, clay, talc, etc. are used for the purpose of preventing stickiness and blocking of the surface of the recording area and adjusting ink bleeding to the extent that the light transmittance of the ink receiving layer is not impaired. Further, fine powders such as calcium carbonate, aluminum silicate, synthetic zeolite, alumina, zinc oxide, cellulose powder and starch powder can be added.
[0023]
The average particle size of these particles is preferably 0.1 μm or more, more preferably 0.3 μm or more. By adding such particles, the slipperiness of the recording medium is improved and the transportability in the printer is improved.
[0024]
The ink receiving layer of the present invention further includes known inorganic pigments, colored dyes, colored pigments, ultraviolet absorbers, antioxidants, dispersants, antifoaming agents, lubricants, fluorescent dyes, preservatives, pH adjusting agents, and the like. Various additives can be added.
[0025]
In the present invention, the ink receiving layer formed on the base material as a support is composed of one layer.
[0026]
The coating method is not particularly limited, and gravure coating method, kiss coating method, dip method, spray coating method, curtain coating method, air knife method, blade coating method, reverse roll coating method, bar coating method and the like are usually used.
[0027]
The coating amount of the ink receiving layer is preferably 5 to 80 g / m ² after drying. More preferably, the amount is 8 to 50 g / m ² . When the coating amount is less than 5 g / m ^2, it is not preferable because the ink receiving layer is thin and the ink cannot be completely absorbed. On the other hand, when the coating amount exceeds 80 g / m ² , the ink is deeply absorbed and the printing density is lowered, which is not preferable.
The ink receiving layer is provided on at least one side of the support, but may be provided on both sides of the support for the purpose of preventing curling.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to examples. In the text, the term “part” is based on the weight in terms of solid content.
[0029]
Reference example 1
As a support, a polyethylene terephthalate film (trade name: manufactured by Melinex 534 DuPont) having a thickness of 100 μm is used, and the coating amount after drying a coating liquid having the following composition on the support is 10 g / m ^2. Thus, it dried on 120 degreeC and the conditions for 2 minutes, and obtained the recording sheet for inkjet.
Coating liquid composition: Polyvinyl alcohol 7.5 parts (PVA 217 Kuraray polymerization degree 1700 saponification degree 88%)
2.5 parts of polyvinylpyrrolidone (made by Rubiscol K-90 BASF)
1.0 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
88.9 parts of water [0030]
Comparative Example 1
An ink jet recording sheet was obtained in the same manner as in Reference Example 1 except that the procedure was performed without adding the surfactant.
[0031]
Reference example 2
An inkjet recording sheet was obtained using the following coating liquid under the same conditions as in Reference Example 1.
Coating liquid composition: Polyvinyl alcohol 7.5 parts (PVA 217 Kuraray polymerization degree 1700 saponification degree 88%)
2.5 parts of polyvinylpyrrolidone (made by Rubiscol K-90 BASF)
0.5 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
89.4 parts of water [0032]
Comparative Example 2
An inkjet recording sheet was obtained in the same manner as in Reference Example 1 except that no cationic compound was used.
[0033]
Comparative Example 3
An inkjet recording sheet was obtained using the following coating liquid under the same conditions as in Reference Example 1.
7.5 parts of polyvinyl alcohol (PVA 217 Kuraray's degree of polymerization 1700 saponification degree 88%)
2.5 parts of polyvinylpyrrolidone (made by Rubiscol K-90 BASF)
Cationic compound 1.5 parts (Smiles resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
88.4 parts of water [0034]
Comparative Example 4
An inkjet recording sheet was obtained using the following coating liquid under the same conditions as in Reference Example 1.
Polyvinyl alcohol 8.0 parts (PVA 217 Kuraray polymerization degree 1700 saponification degree 88%)
Polyvinylpyrrolidone 2.0 parts (Lubicol K-90 BASF)
0.5 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
89.4 parts of water [0035]
Example 3
An inkjet recording sheet was obtained using the following coating liquid under the same conditions as in Reference Example 1.
Polyvinyl alcohol 5.0 parts (PVA 217 Kuraray polymerization degree 1700 saponification degree 88%)
Polyvinylpyrrolidone 5.0 parts (Lubicol K-90 BASF)
1.0 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
88.9 parts of water [0036]
Example 4
An inkjet recording sheet was obtained in the same manner as in Reference Example 1 using the following coating liquid.
Polyvinyl alcohol 2.5 parts (polymerization degree 1700 made by PVA 217 Kuraray saponification degree 88%)
7.5 parts of polyvinylpyrrolidone (made by Rubiscol K-90 BASF)
1.0 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
88.9 parts of water
Comparative Example 5
An inkjet recording sheet was obtained using the following coating liquid under the same conditions as in Reference Example 1.
Polyvinyl alcohol 2.0 parts (PVA 217 Kuraray polymerization degree 1700 saponification degree 88%)
8.0 parts of polyvinylpyrrolidone (made by Rubiscol K-90 BASF)
1.0 part of cationic compound (Smileds resin 1001 manufactured by Sumitomo Chemical Co., Ltd.)
Fluorosurfactant 0.1 parts (Megafac F-142D manufactured by Dainippon Ink)
88.9 parts of water [0038]
The samples obtained in Examples, Reference Examples and Comparative Examples were evaluated by the following evaluation methods using an ink jet printer (Epson MJ-930C) and dedicated ink.
(Ink drying property) Print a high quality uniform image of blue (B), green (G), red (R), black (K), and after 3 minutes, 10 minutes and 1 hour, In addition, the degree of ink transfer onto fine paper was visually observed and determined.
A: Slight transfer of K is observed after 3 minutes, but no transfer is observed after 10 minutes and 1 hour, and there is no practical problem.
○: B, G, R, and K are slightly transferred after 3 minutes, but transfer is not performed at all after 10 minutes and 1 hour.
Δ: Transfer of any of B, G, R, and K is recognized after 10 minutes, but transfer is not allowed at all after 1 hour, and is a practically acceptable limit level.
X: Transfer of any of B, R, G, and K is recognized even after 1 hour, and cannot be used practically.
[0039]
(Uneven density)
(Double-circle): It is very excellent with almost no spotted density unevenness.
○: A level where there is a slight problem of spotted density unevenness but there is no practical problem.
Δ: Spotted density unevenness is observed, but it is a practically acceptable limit level.
X: Spotted density unevenness is noticeable and cannot be used practically.
[0040]
(Brightness at high temperature)
Letters are printed at the maximum density of yellow (Y), magenta (M), cyan (C), and black (B), and the appearance of the letters on the sample left in an environment of 35 ° C. and 80% RH for 24 hours is visually observed. Was observed and judged.
A: Characters are not completely blurred and are very excellent.
○: Slightly blurs characters, but at a level where there is no practical problem.
Δ: Characters are blurred, but can be identified and practically acceptable.
X: Characters are blurred and cannot be identified and practically used.
[0041]
[Table 1]
[0042]
【The invention's effect】
The ink jet recording sheet according to the present invention is superior in ink absorbability and drying property to a high speed, high discharge amount ink jet printer, has high image quality without density unevenness, and further, can be used for long-term storage of printed matter or high temperature and high humidity. Excellent storage stability, improves bleeding and has an excellent effect.

Claims (2)

In the ink jet recording sheet having one ink-receiving layer containing a water-soluble polymer and a compound having a cationic group on the surface of a transparent film support , the water-soluble polymer has a saponification degree of 75 to 90%. of polyvinyl alcohol and the ratio of polyvinyl pyrrolidone 50: 50-25: 75 a mixture of 0.5 to 1 mixing ratio of the compound having the cationic group to said water-soluble polymer 10.0 parts by weight. An ink jet recording sheet comprising 0 part by mass and containing a surfactant in the ink receiving layer.   2. The ink jet recording sheet according to claim 1, wherein the surfactant is a fluorosurfactant.