JPH06143793A - Ink-jet recording sheet and recording thereof - Google Patents

Abstract

PURPOSE:To constitute the method so that an image which is superior in absorbing properties of ink, had a high image density and obtain a clear image. CONSTITUTION:This is an ink-jet recording sheet which is obtained by making use of a substrate wherein a permeation time of ink for ink-jet recording through the substrate is not exceeding 60 seconds, preferably 0.1-30 seconds and providing an ink receiving layer having a coating quantity of 1-10g/m<2> the substrate. Then, this is a recording method for which the ink-jet recording sheet is used.

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 for recording with ink, more specifically, ink jet recording having excellent ink absorbency and high density and sharpness of recorded image. It is about the seat. The present invention also relates to an inkjet recording method for recording using the inkjet recording sheet.

[0002]

2. Description of the Related Art Ink jet recording is a system in which minute droplets of ink are ejected by various operating principles and adhered to a recording sheet such as paper to record images, characters, etc. It has features such as easy multicoloring, great flexibility in recording patterns, and no need for development-fixing. It is rapidly spreading in various applications as a recording device for various figures and color images including Chinese characters. . Further, an image formed by the multicolor ink jet system can obtain a recording comparable to that of the multicolor printing by the plate making system or the printing by the color photographic system. Further, in applications requiring a small number of copies, it is being widely applied to the field of full-color image recording because it is cheaper than the photographic technique.

As a recording sheet used in this ink jet recording system, efforts have been made from the viewpoint of the apparatus and the ink composition in order to use high-quality paper or coated paper which is used for ordinary printing and writing. However, with the improvement of the performance of the inkjet recording apparatus and the expansion of its uses such as the speeding up of the apparatus, the increase in the definition and the increase in the full color, more advanced characteristics have been required for the recording sheet. That is, as the recording sheet, the density of print dots is high, the color tone is bright and vivid, the ink does not flow out or bleed even when the print dots overlap due to fast ink absorption, and the print dots It is required that the horizontal diffusion is not unnecessarily large and that the periphery is smooth and not blurred.

As the form of the ink jet recording sheet, plain paper type and paper such as high quality paper, synthetic paper, synthetic resin film, etc., in which ink is absorbed in a support typified by so-called high quality paper, bond paper, etc. It is roughly classified into a coat type in which an ink receiving layer is provided on the body surface.

For the coat type, an ink jet recording sheet having a low coating amount of about 1 to 10 g / m ² , 10 to 20 g
/ M ² Inkjet recording sheet with medium coating amount, 2
There is an ink jet recording sheet having a high coating amount of 0 g / m ² or more. In particular, as a support mainly composed of pulp fibers and fillers, it is possible that a base paper having a Steckigt sizing degree of 0 to several tens of seconds is coated in various combinations with the coating amount according to the ink adhesion amount. To be Especially for color recording,
Not only single-color recording of yellow, magenta, cyan, and black, but also superposition of these colors for multi-color recording, and the amount of ink deposited is extremely large.Therefore, when the coating amount is low, the ink is absorbed by the coating layer. Since the paper cannot be cut off, it is necessary to use a base paper having a relatively low size and to absorb a part of the ink adhered to the support.

To solve these problems, Japanese Patent Publication No.
JP-A-26665 discloses an example of an ink jet recording paper in which a coating layer containing fine silica particles and a water-soluble polymer binder is provided on a base paper having a basis weight of 60 g / m ² and a Steckigt sizing degree of 4 seconds or less. Was announced, and Japanese Patent Laid-Open No. 59-3808
7 publication, on a base material having a size degree of 0 to 10 seconds,
An example of an ink jet recording material provided with an ink absorbing layer is disclosed, and JP-A-59-95186 discloses an example of an ink jet recording paper in which a base paper having a Steckigt size degree of 0 to 5 seconds is impregnated with polyvinylpyrrolidone or the like. Has been done.

[0007]

As described above, when the ink receiving layer has a low coating amount, the coating layer cannot absorb the ink so that the base paper having a relatively low size is used as the support. It is also necessary to absorb a part of the attached ink. However, there is often no correlation between the previously proposed Steckigt sizing degree of the support and the ink absorbency at the time of actual recording. It is impossible to predict the quality of the captured image. This is because water is the only solvent when measuring the Steckigt sizing degree, and the recording ink for inkjet recording contains water, an organic solvent other than water, and other additives, and the ink viscosity, surface tension, permeability, etc. This is because various inks have different physical properties.
That is, it is essential to form a support and a coating layer in accordance with various inkjet recording inks, and it is necessary to measure the ink permeation time of the support in the ink actually used for recording.

An object of the present invention is to control the ink permeation time of the support within a specific range so that the ink density and the image clarity are not impaired even when the ink receiving layer has a low coating amount. It is to obtain an ink jet recording sheet having good absorption. Furthermore, by recording with the recording ink on the inkjet recording sheet,
To get a good quality image.

[0009]

That is, the ink jet recording sheet of the present invention has a support having a basis weight of 60 g / m ² as a reference, and the support is allowed to stand on the liquid surface of the ink for ink jet recording, An ink receiving layer having a coating amount of 1 to 10 g / m ² is provided on the support having an ink permeation time of 60 seconds or less from the surface in contact with the liquid surface to the surface opposite to the liquid surface. It is characterized by.

Further, the ink jet recording sheet of the present invention is characterized in that the ink permeation time of the support is 0.1 to 30 seconds.

Further, it is an ink jet recording method for recording using the ink jet recording sheet.

In the present invention, the ink permeation time of the support is 60 seconds or less based on a basis weight of 60 g / m ² , that is, the value of ink permeation time (second) / grammage (g / m ² ) is 1 or less. is there. Therefore, for example, when the basis weight of the support is 100 g / m ² , the ink permeation time is required to be 100 seconds or less.

Examples of the support used in the present invention include paper mainly composed of wood fibers, and sheet-like substances such as non-woven fabrics composed mainly of wood fibers and synthetic fibers. In the case of paper, addition of an internal sizing agent is used. Alternatively, no addition, use of a sizing agent such as a neutral sizing agent, a polymer sizing agent, or an acidic sizing agent, alone or in combination, and inclusion or non-inclusion of a filler may be used, with or without size pressing. As the internal filler for the paper support, conventionally known pigments are used as white pigments, and they can be used alone or in combination, and examples thereof include light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate,
Barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic silica,
White inorganic pigments such as aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide, styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, organic pigments such as urea resin, melamine resin, etc. Can be mentioned.

In the present invention, one or more known white pigments may be used in the ink receiving layer. For example,
Light calcium carbonate, heavy calcium carbonate, kaolin,
Talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white,
Aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica,
Colloidal alumina, pseudo-boehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrohalloysite, magnesium carbonate, white inorganic pigments such as magnesium hydroxide, styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin, melamine Examples include organic pigments such as resins. Among the above, as the white pigment contained as a main component in the ink receiving layer, a porous inorganic pigment is preferable,
Examples thereof include porous synthetic amorphous silica, porous magnesium carbonate, porous alumina, and the like, and porous synthetic amorphous silica having a large pore volume is particularly preferable. Furthermore, instead of white pigment, raw starch particles, such as corn (corn starch), wheat, barley, rice, potato (potato), cassava (tapioca), sweet potato (sweet potato), sago, etc., are not soluble in cold water or scarcely present. It is also possible to use raw starch particles.

Examples of the adhesive used in the ink-receiving layer of the present invention include polyvinyl alcohol, vinyl acetate, oxidized starch, etherified starch, carboxymethyl cellulose, cellulose derivatives such as hydroxyethyl cellulose, casein, gelatin, soybean protein, Silyl-modified polyvinyl alcohol, etc .; maleic anhydride resin, styrene-
Conjugated diene copolymer latex such as butadiene copolymer and methyl methacrylate-butadiene copolymer; acrylic polymer latex such as polymer or copolymer of acrylic acid ester and methacrylic acid ester; ethylene vinyl acetate copolymer Polymer latex such as vinyl polymer latex; or functional group-modified polymer latex with monomers containing functional groups such as carboxyl groups of these various polymers; water-based adhesive such as thermosetting synthetic resin system of melamine resin, urea resin, etc. ; Polymethylmethacrylate, polyurethane resin, unsaturated polyester resin, vinyl chloride-vinyl acetate copolymer,
Synthetic resin adhesives such as polyvinyl butyral and alkyd resin can be mentioned, and they are used in one kind or more. Of these, water-soluble polymer binders are preferably used in the present invention.

One or more cationic dye fixing agents can be used in the ink receiving layer of the present invention. The cationic dye fixing agent is a monomer, oligomer or polymer of a primary to tertiary amine or a quaternary ammonium salt that disintegrates when it is dissolved in water to exhibit a cationic property, and is preferably an oligomer or polymer.

In the present invention, as other additives,
Pigment dispersant, thickener, fluidity improver, defoamer, foam suppressor,
Release agents, foaming agents, penetrants, coloring dyes, coloring pigments, optical brighteners, ultraviolet absorbers, antioxidants, preservatives, antifungal agents,
A water resistance agent, a wet paper strength enhancer, a dry paper strength enhancer and the like can be appropriately blended.

As a method for producing the ink jet recording sheet of the present invention, for example, pulp fibers are disintegrated into a slurry, and if necessary, a filler, a sizing agent and other additives are added, papermaking is carried out by a paper machine and dried. Alternatively, after the papermaking, an aqueous solution of starch or a polymer substance is size-pressed, dried and machine-calendered to obtain a support sheet, and at least one layer or more is applied using a coating device or a size press device. An ink receiving layer is provided. The maximum heating temperature of the dryer is at least 100 ° C or higher, preferably 120 ° C or higher. It is preferable that the temperature is high in relation to the drying efficiency, but the temperature is not particularly limited. The machine calendar may or may not be used, but it is preferably used in consideration of workability in the next coating step. The method for providing the ink receiving layer may be either an on-machine coater or an off-machine coater. For example, conventionally known air knife coaters, curtain coaters, die coaters, blade coaters, gate roll coaters, bar coaters, rod coaters, roll coaters, bill blade coaters, short dwell blade coaters and the like can be used. Further, after coating, finish using a calendar such as a machine calendar, super calendar, or soft calendar.

In the present invention, a back coat layer may be provided on the surface opposite to the ink receiving layer. The composition of the back coat layer may or may not be the same as the composition of the ink receiving layer, and the coating amount, the coating method and the like are not particularly limited.

The ink jet recording ink referred to in the present invention is a recording liquid containing the following coloring agent, liquid medium and other additives. Examples of the colorant include water-soluble dyes such as direct dyes, acid dyes, basic dyes, reactive dyes and food dyes.

As the solvent of the aqueous ink, water and various water-soluble organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, C1-C4 alkyl alcohols such as isobutyl alcohol; amides such as dimethylformamide and dimethylacetamide; ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyethylene glycol, polypropylene glycol Polyalkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hex Alkylene glycols having 2 to 6 alkylene groups such as len glycol and diethylene glycol; lower alkyl ethers of polyhydric alcohols such as glycerin, ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether and triethylene glycol monomethyl ether Can be mentioned. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether are preferable. Other additives include, for example, P
Examples include H regulators, sequestering agents, fungicides, viscosity regulators, surface tension regulators, wetting agents, surfactants, and rust inhibitors.

The ink jet recording sheet according to the present invention is not limited to use as an ink jet recording sheet, and may be used as any recording sheet using a liquid ink during recording. For example, an ink sheet in which a heat-fusible ink containing a heat-fusible substance, a dye or pigment as a main component is applied on a thin support such as a resin film, high-density paper, or synthetic paper is heated from the back side of the ink sheet to remove the ink. An image-receiving sheet for thermal transfer recording that is melted and transferred, an inkjet recording sheet that heat-melts a heat-meltable ink to form fine droplets and performs flight recording, an inkjet recording sheet that uses an ink in which an oil-soluble dye is dissolved in a solvent, photopolymerization Examples thereof include an image receiving sheet corresponding to a light and pressure sensitive donor sheet using microcapsules containing a type monomer and colorless or colored dyes and pigments. The common features of these recording sheets are
The point is that the ink is in a liquid state during recording. The liquid ink penetrates or spreads in the depth direction or the horizontal direction of the ink receiving layer of the recording sheet before being cured, solidified, or fixed. The various recording sheets described above require absorptivity according to their respective systems, and the inkjet recording sheet of the present invention may be used as the various recording sheets described above.

Further, the ink jet recording sheet according to the present invention may be used as a recording sheet for heating and fixing toner of the electrophotographic recording system which is widely used in copying machines, printers and the like.

Further, the "ink permeation time" according to the present invention will be described in detail. The measurement is performed using an inkjet recording ink and a piece of paper (support) whose humidity has been adjusted to 20 ° C. and 65% RH. Measure the time from the moment a piece of paper floats on the ink for inkjet recording placed in a petri dish to the time when the ink penetrates and three spots of ink appear on the opposite surface (upper surface). Transmission time. The measurement is performed on both sides of a piece of paper (support), and the average value is shown.

[0025]

In the ink jet recording sheet of the present invention, the support is allowed to stand on the ink surface of the ink jet recording ink which is actually used, and the ink permeation time to the opposite surface (upper surface) of the support is The amount of 60 g / m ² is 60 seconds or less, preferably O. The coating amount is 1 to 1 on the support which is 1 to 30 seconds.
By providing an ink receiving layer of 10 g / m ² ,
It was possible to obtain an inkjet recording sheet having good ink absorbability without impairing image density and image clarity.

[0026]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples.
In addition, "parts" and "%" shown in the examples represent parts by weight and% by weight, unless otherwise specified.

The amount of AKD (alkyl ketene dimer, Hacon 603S; manufactured by Dick Hercules), the amount of filler (light calcium carbonate, TP-121) was applied to pulp having a freeness of 450 ml CSF LBKP / freeness of 480 ml CSF NBKP = 9/1. Oil absorption 90 to 100
g / 100g, BET specific surface area of ^{2 to} 4 m ² / g, spindle-shaped calcite type crystal structure having an average particle size of 0.4 × 2.0 μm; manufactured by Okutama Kogyo Co., Ltd., size press liquid (oxidized starch MS-380)
0; manufactured by Nippon Shokuhin Kako Co., Ltd.)
Such that / m ² to papermaking with Fourdrinier paper machine to obtain a support of Examples and Comparative Examples.

The ink receiving layer was composed of 50 parts of synthetic amorphous silica (Fineseal X-37B; manufactured by Tokuyama Soda Co., Ltd.), 50 parts of rice starch powder (micropol; manufactured by Shimada Chemical Co., Ltd.), polyvinyl alcohol (PVA117; 30 parts of Kuraray Co., Ltd.) and 30 parts of a cationic dye fixing agent (Sumiless Resin 1001; Sumitomo Chemical Co., Ltd.) were mixed onto each support so that the coating amount would be 5 g / m ^2. Was applied to the above to give a super calender finish to obtain inkjet recording sheets of Examples and Comparative Examples.

Regarding the ink permeation time, the ink for ink-jet recording and the paper piece (support) whose humidity was adjusted to 20 ° C.-65% RH were used, and the ink for ink-jet printer actually recorded was black, cyan, magenta, or yellow. The measurement was performed for four colors and the average value was shown. If the ink cannot be measured because the ink penetrates instantly, 0 seconds
At 80 seconds, no ink permeation was recorded as 3 minutes or more.

The ink absorbency and the sharpness of the image are determined by visually observing the degree of ink bleeding at the boundary between the heavy solid print areas, for example, the boundary area between the red print (magenta + yellow) and the green print (cyan + yellow). It was judged. When the red printed portion and the green printed portion did not overlap and were separated, the characteristics were good, and when the overlapping was large and a black line was formed, the characteristics were bad. A substance having poor ink absorbability remarkably impairs image quality (image sharpness), so that it does not make any sense even if other properties such as image density are good.

The image density was measured by using a reflection densitometer (Macbeth RD918; manufactured by Macbeth Co.) on a portion solidly printed with black ink. The higher the value, the higher the image density and the better, but normally, 1.20 or more is good.

Examples 1 to 4 and Comparative Examples 1 to 4 Table 1 shows the content of the support used in Examples 1 to 4 and Comparative Examples 1 to 4 (AKD amount, filler amount, oxidized starch adhesion amount). ,
Steckigt sizing degree, ink permeation time, and an ink jet recording sheet provided with an ink receiving layer on each support,
The inkjet recording characteristics when recorded using a genuine inkjet recording ink of IO-720 printer manufactured by Sharp were shown.

[0033]

[Table 1]

In Table 1, * 1 and * 2 are as follows. A: Shows good characteristics. B: Good in a range where there is no practical problem. C: Shows that there is a problem in practical use. D: Characteristic failure is shown. In Table 1, the amount of AKD and the amount of filler are% by weight based on the total solid amount of the support, and the amount of oxidized starch is the oxidized starch solid amount (g / m ² ) impregnated during size pressing.

Examples 5 to 11 and Comparative Example 5 Table 2 shows the contents of the support used in Examples 5 to 11 and Comparative Example 5 (the amount of AKD, the amount of filler, the amount of oxidized starch deposited), and the Steckit size. The ink jet recording characteristics when recorded with a genuine ink jet recording ink by a Sharp IO-735X printer on an ink jet recording sheet provided with an ink receiving layer on each support are shown.

[0036]

[Table 2]

In Table 2, * 1 and * 2 are as follows. A: Shows good characteristics. B: Good in a range where there is no practical problem. C: Shows that there is a problem in practical use. D: Characteristic failure is shown. In Table 1, the amount of AKD and the amount of filler are% by weight based on the total solid amount of the support, and the amount of oxidized starch is the oxidized starch solid amount (g / m ² ) impregnated during size pressing.

Examples 12 to 16 and Comparative Examples 6 to 8 In Table 3, the content of the support used in Examples 12 to 16 and Comparative Examples 6 to 8 (AKD amount, filler amount, oxidized starch adhesion amount) is shown. , Steckigt sizing degree, ink permeation time, and inkjet recording characteristics when recording with a genuine inkjet recording ink with a Canon BJC-820J printer on an inkjet recording sheet provided with an ink receiving layer on each support. Indicated.

[0039]

[Table 3]

In Table 3, * 1 and * 2 are as follows. A: Shows good characteristics. B: Good in a range where there is no practical problem. C: Shows that there is a problem in practical use. D: Characteristic failure is shown. In Table 1, the amount of AKD and the amount of filler are% by weight based on the total solid amount of the support, and the amount of oxidized starch is the oxidized starch solid amount (g / m ² ) impregnated during size pressing.

As is clear from Examples 1 to 16 and Comparative Examples 1 to 8, there is no correlation between the Steckigt sizing degree and the ink absorptivity, and there is a good correlation between the ink permeation time and the ink absorptivity. To be Also, the same recording sheet, for example,
Also in Comparative Example 1, Example 5, and Example 12, the ink permeation time becomes long depending on the ink used for inkjet recording. That is, the ink permeation time of the inkjet recording ink actually used for recording is 60
An ink jet recording sheet having good ink absorbability could be obtained by using a support of not more than a second. Furthermore, by using a support having an ink permeation time of 0.1 to 30 seconds, the image density and image clarity are not impaired,
An ink jet recording sheet having good ink absorbability could be obtained.

[0042]

In the ink jet recording sheet of the present invention, the ink permeation time to the opposite surface (upper surface) when the support sheet is left standing on the ink surface of the ink jet recording ink actually used is 6 based on 60g / m ²
By providing an ink receiving layer having a coating amount of 1 to 10 g / m ² on a support for 0 seconds or less, preferably 0.1 to 30 seconds, without impairing image density and image sharpness. It was possible to obtain a recorded image with good ink absorption.

Claims (3)

[Claims] 1. A support having a basis weight of 60 g / m ² is used as a reference, and the support is allowed to stand still on the liquid surface of the ink for ink jet recording, and the support is moved from the surface in contact with the liquid surface to the opposite surface. An ink jet recording sheet comprising an ink receiving layer having a coating amount of 1 to 10 g / m ² provided on the support having an ink passing time of 60 seconds or less. 2. The ink permeation time of the support is 0.1 to 10.
The inkjet recording sheet according to claim 1, wherein the recording time is 30 seconds. 3. A support having a basis weight of 60 g / m ² is used as a reference, and the support is allowed to stand still on the liquid surface of the ink for ink jet recording, and from the surface in contact with the liquid surface to the opposite surface. An ink jet recording method comprising recording using an ink jet recording sheet having an ink receiving layer having a coating amount of 1 to 10 g / m ² on the support having an ink passing time of 60 seconds or less.