JPS62242577A - Recording material and recording method using the same - Google Patents

Abstract

PURPOSE:To provide a moderate surface luster and record images with excellent image density, by setting to within a specified range the weight ratio of particles non-dyeable with a recording agent to a binder. CONSTITUTION:In use of a recording material, images are recorded in an ink on an ink-transporting layer provided on the recording side, and are observed from the side of an ink-holding layer provided on the observing side. The ink- transporting layer comprises particles non-dyeable with a recording agent and a binder as main constituents, in a weight ratio of the particles to the binder of 1/3-30/1, permits liquids to penetrate therethrough, and has the function of rapidly absorbing the ink adhered to the surface thereof and permitting the ink to penetrate therethrough. The ink-holding layer functions to absorb and hold the ink or the recording agent transferred from the ink-transporting layer. If the quantity of the binder is excessively large, the number of cracks or open cells in the ink-transporting layer is reduced, and an ink-absorbing effect is reduced. If the quantity of the particles is excessively large, through the void ratio of the ink-transporting layer is raised, image quality is lowered, and further, the strength of the layer is lowered or it is impossible to form the film of the layer.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to recording materials suitable for recording methods using ink, such as felt-tip pens, fountain pens, pen plotters, and inkjet recording devices, particularly those having an ink-absorbing property. The present invention also relates to a recording material with excellent color properties of recorded images and a recording method for obtaining high quality recorded images.

(Prior Art) Conventionally, recording methods using ink, such as writing with a fountain pen, felt pen, ballpoint pen, etc., pen plotter,
The recording material used for recording with an inkjet recording device or the like is general paper such as high-quality paper, bond paper, writing paper, or art paper.

Examples include coated paper such as cast coated paper.

However, in recent years, with the development of recording Qa devices such as inkjet recording devices and pen plotters, sufficient recording characteristics cannot be obtained with the above-mentioned conventional recording materials.

In other words, in recent recording methods such as those described above, high-speed recording and multi-color recording are performed that are incomparable to conventional methods.
Conventional recording materials have not reached a satisfactory level in terms of ink absorption, color development when a plurality of inks stick to the same location, chromaticity, and the like.

In order to solve these problems, coated paper having a porous ink-absorbing layer on the surface of the base material, such as inkjet paper, has been devised.
Japanese Patent No. 214989 describes a sheet having a porous ink-absorbing resin layer provided on a base material.

This ink absorption layer is porous and contains pores and cracks inside, which improves the ink absorption speed.

In this way, by providing a porous ink absorption layer,
Although it is possible to increase ink absorption to some extent,
Since the absorption layer is porous, the recording material has light diffusing properties, making it impossible to obtain clear recorded images with high optical density and glossy recorded images.

In addition, since the recorded image is observed from the ink recording surface, the recording agent is configured to remain as much as possible on the surface of the absorbing layer, which has the disadvantage that the durability and storage stability of the image, such as water resistance and abrasion resistance, are inferior. There is.

One known method for solving this problem is a recording medium disclosed in, for example, Japanese Patent Laid-Open No. 136480/1983. This recording medium has at least one highly white ink-receiving layer provided on a support, and the formed image is observed from the support. In this method, various performances such as water resistance on the viewing surface have been sufficiently resolved, but a large amount of face paint 4 is used to increase the whitening of the ink receiving layer, and as a result, although the whitening is high, The attached ink is adsorbed by the pigment.

The amount of ink that reaches the interface between the ink-receiving layer and the support is reduced, reducing the image density on the viewing surface!・It has the disadvantage that it cannot be made very high, and its color quality and resolution are also inferior.

In addition, recently, as the speed and quality of recording using inkjet recording devices, pen plotters, etc. has increased, there has been a demand for recording materials with dramatic recording performance.

In other words, the absorbency of ink and the color development of recording material.

There is now a need for recording materials that are significantly superior to conventional recording materials in all aspects of recording properties, such as image quality of recorded images, resolution, chromaticity, recorded image density, and gloss.

As a result of research in order to provide a recording material as described above, the present inventor has discovered a material having a specific structure, which has a liquid-permeable ink transport layer and an ink retention layer, and in which the recording surface and the image observation surface are in a front-back relationship. I previously suggested recording materials.

However, in the recording materials of these prior inventions,
The correlation between various required performances, such as the ink absorption strength of the formed ink transport layer, the relationship with the ink retention layer, and the relationship with the quality of the formed image, is not clear, and it is difficult to improve certain properties. For example, if the thickness of the ink transport layer is increased to improve ink absorption, the image density will decrease, and if it is too high, the resolution will decrease. When too many particles are added, cracks occur in the ink transport layer and powder falls off severely, while when too few particles are added, various problems occur such as insufficient ink absorbency.

Therefore, the above-mentioned recording materials exhibit flat ink absorbency, water resistance, blocking resistance, etc. during recording, and after recording, they exhibit image quality such as excellent color, high image density, and resolution. There is a demand for a recording material that can provide an image that has the same characteristics as those described above.

(Problems to be Solved by the Invention) However, at present, a recording material that simultaneously satisfies all of these recording characteristics has not yet been obtained.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a recording material that has an appropriate gloss on its surface and allows recording images with excellent image density to be obtained.

A further object of the present invention is to provide a recording material from which recorded images can be obtained that are excellent in water resistance, abrasion resistance, storage stability, visibility, and the like.

Still another object of the present invention is to provide a recording method that allows the above-mentioned high-quality recorded images to be easily obtained.

” Two objectives are achieved by the invention as follows.

(Means for Solving the Problems) That is, the first aspect of the present invention is a recording material having an ink transport layer and an ink retention layer, wherein the ink transport layer is non-stainable to the recording agent. This recording material is mainly composed of particles and a binder, and is characterized in that the weight ratio of the particles to the binder is in the range of 1/3 to 50/1.

Furthermore, a second aspect of the present invention is a recording method for recording with ink on the recording surface of a recording material having an ink transport layer and an ink holding layer, wherein the ink transport layer is in contact with the recording material. This recording method is mainly composed of non-dying particles and a binder, and is characterized in that the weight ratio of the particles to the binder is in the range of 1/3 to 50/l.

In other words, as a result of intensive research to solve the unclear points of the prior invention as described above, the inventors of the present invention have discovered that a transparent substrate is used in recording materials in which recording is performed from the ink transport layer and one image is observed from the back side. According to Murakami, forming an ink transport layer from a specific proportion of particles and a binder increases the film strength of the ink transport layer,
Ink absorbency is the most important factor for image quality after recording, and the ratio of such particles to binder should be within a specific range, that is, from 1/3 to 50/l. The present invention was completed based on the finding that it is possible to achieve both excellent ink absorption during recording, excellent image quality after recording, and film strength of the ink transport layer before and after recording.

(Function) The recording material of the present invention is different from conventional recording materials in which the recording surface and the viewing surface are the same, and the recording surface and the viewing surface are in a front-back relationship.

That is, in the recording material of the present invention, recording is basically performed using ink on the ink transport layer, which is the recording side, and the recorded image is observed from the ink retaining layer side, which is the viewing side.

The ink transport layer that primarily characterizes the present invention is formed mainly of particles and a binder, has liquid permeability, and has the function of quickly absorbing and transmitting ink attached to its surface. On the other hand, the ink retention layer has a function of absorbing and retaining ink or recording material transferred from the ink transport layer.

At this time, the ink transport layer must have high affinity for the liquid medium in the ink, and at the same time, the recording agent (dye,
On the contrary, it must have a low affinity for colorants such as pigments and materials with color-forming properties.

Therefore, the ink transport layer is constructed by selecting a material that has properties such as wetting, penetration, and diffusion for the ink medium, but does not have properties such as adsorption, penetration, and reaction for the recording material. It must be.

In the recording material of the present invention, the above-mentioned effects are suitably exhibited by forming the ink transport layer from particles and a binder in a weight ratio ranging from 1/3 to 50/l.

The ink retaining layer, which is the second feature of the present invention, must have a stronger ability to absorb ink than the ink transport layer in order to stably absorb and capture the ink temporarily absorbed by the ink transport layer.

Therefore, the ink retaining layer must have high affinity for the recording agent as well as for the ink medium.

Hereinafter, the present invention will be explained in more detail based on preferred embodiments.

The recording material of the present invention includes a base material as a support.

an ink retaining layer formed on the Omura that substantially absorbs and captures ink or a recording agent, and an ink retaining layer formed on the ink retaining layer that directly receives ink, has liquid permeability, and substantially absorbs and captures the recording agent. Constructed of an ink transport layer that leaves no residue.

However, if the ink transport layer or the ink retention layer also functions as a base material, the base material is not necessarily required.

As the base material used in the present invention, any conventionally known base material can be used, and specifically, polyester resin, diacetate resin, triacetate resin, polystyrene resin, polyethylene resin, polycarbonate resin, polysulfone resin, polymethacrylate resin, Examples include plastic films, plates, and glass plates such as cellophane, celluloid, polyvinyl chloride resin, polyvinylidene chloride resin, and polyimide resin. The thickness of these base materials may be any thickness, but is generally about 1 pm to 5.000 ILm.

Note that, as described above, in the present invention, since a recorded image is observed from the side opposite to the recording side, the base material needs to have light-transmitting properties.

In addition, the base material used may be subjected to any processing as long as it finally has translucency. For example, the base material may be given a desired pattern, an appropriate gloss, or a textured pattern. It is possible to apply Furthermore, by selecting a base material having water resistance, abrasion resistance, etc., it is also possible to impart water resistance, abrasion resistance, etc. to the image observation surface of the recording material.

In order for the ink transport layer constituting the recording material of the present invention to exhibit appropriate liquid permeability and sufficient film strength of the ink transport layer,
It is necessary to form particles and a binder at a weight ratio of 1/3 to 50/l. Appropriate liquid permeability as used in the present invention means that the ink should be formed by adjusting the ink absorbency of the ink retaining layer. The term "sufficient film strength of the ink transport layer" refers to the property of not allowing the recording agent in the ink to substantially remain in the ink transport layer, while having sufficient liquid permeability as described above.

A preferred embodiment for achieving both liquid permeability and film strength of the ink transport layer, which refers to the strength of the particles forming the ink transport layer to prevent them from falling off during normal handling, is to adjust the ratio of the particles to the binder. The objective is to form a porous structure having appropriate cracks and communicating pores inside the ink transport layer while maintaining the film strength of the ink transport layer.

Furthermore, as described above, in the present invention, in order to observe a reflective recorded image from the opposite side of the recording surface, it is preferable that the ink transport layer has light diffusing properties.

The ink transport layer satisfies the above characteristics.

Preferably, it mainly consists of particles that do not stain the recording material and a binder.

Such particles include the recording agent in the ink, that is,
Any particles may be used as long as they do not substantially adsorb dyes, etc., and particularly suitable particles in the present invention include highly hydrophobic thermoplastic resins, thermoplastic resins, etc., since dyes in inks are generally water-soluble. Organic particles such as curable resins, such as polystyrene, polymethacrylate, elastomer, ethylene-vinyl acetate polymer, styrene-acrylic copolymer, polyester, polyacrylic, polyvinyl ether,
At least one of resin powders such as polyamide, polyolefin, guanamine, and SBR, and their emulsions and suspensions may be used as desired. The particle size of such resin particles is preferably in the range of 0.1 to 11003i.

Further, in order to increase the whiteness of the ink transport layer, a white inorganic pigment may be added to an extent that does not impede the ink permeability of the ink transport layer.

Further, the binder used has a function of binding the particles to each other and/or to the ink retaining layer, and is preferably non-staining to the recording material like the single particles.

Preferred materials for the binder include any conventionally known materials as long as they have the properties described above, such as polyvinyl alcohol, acrylic resin, and styrene.
Acrylic copolymer, ethylene-vinyl acetate copolymer, starch, polyvinyl butyral, gelatin, casein,
One or more resins such as ionomer, gum arabic, carboxymethylcellulose, polyvinylpyrrolidone, polyacrylamide, phenol, melanin, epoxy, styrene-butadiene rubber, urea resin, phenolic resin, α-olefin resin, chloroprene, nitrile rubber, etc., as desired. Can be used.

Furthermore, in order to improve the properties of the ink transport layer, various additives such as surfactants, penetrants, etc. may be added to the ink transport layer, if necessary.

The mixing ratio (weight ratio) of the particles and the binder is preferably in the range of particles/binder = l/3 to 50/l, more preferably in the range of 3/l to 20/l. . If there is too much binder in this mixing ratio, there will be fewer cracks and communicating pores in the ink transport layer, reducing the ink absorption effect, and if there are too many particles in this mixing ratio, the porosity will be high. However, the image quality deteriorates, and furthermore, the adhesion between the particles or between the particles and the ink retaining layer becomes insufficient, resulting in a decrease in the strength of the ink transport layer and the inability to form a film.

The thickness of the ink transport layer depends on the amount of ink droplets, but is preferably 24 m or more, more preferably 3 to 80 m.

Next, the non-porous ink retention layer that substantially captures the ink or recording agent absorbs and captures the recording agent in the ink that has passed through the ink transport layer, and substantially permanently retains the recording agent.

The ink retaining layer needs to have a stronger ink absorption ability than the ink transport layer. This is because when the absorption power of the ink retention layer is weaker than the absorption strength of the ink transportation layer, the ink attached to the surface of the ink transportation layer passes through the ink transportation layer, and the tip of the ink passes through the ink transportation layer. When the ink reaches the ink transport layer, the ink stays in the ink transport layer, so that the ink permeates and diffuses in the ink transport layer in the lateral direction at the interface between the ink transport layer and the ink retention layer. As a result, the resolution of the recorded image decreases, making it impossible to form a high-quality recorded image.

Furthermore, as described above, since the recorded image is observed from the side opposite to the recording surface, the ink retaining layer is preferably light-transmissive.

An ink retaining layer that satisfies the above requirements is a light-transmitting resin that adsorbs the recording agent and/or is soluble in the ink.
Preferably, it is made of a light-transmitting resin that has swelling properties.

For example, when a water-based ink containing an acid dye or a direct dye is used as the recording material, the ink-retaining layer is made of a resin that has adsorption properties for the dye, such as a water-soluble resin that has swelling properties for the water-based ink. It is preferable that the ink retaining layer is made of a lignophilic polymer.The material constituting the ink retaining layer is not particularly limited as long as it has the function of absorbing and trapping ink and can form a non-porous layer. It's not something you can do.

The thickness of the ink retaining layer is sufficient as long as it absorbs and traps ink, and although it varies depending on ink dripping, it is preferably 1 to 50 ILm, more preferably 3 to 2 ILm.
It is 04m.

The material constituting the ink retaining layer may be any material as long as it can absorb water-based ink and retain the coloring material in the ink. Examples of such water-soluble or hydrophilic polymers, which are preferably formed from natural polymers, include albumin, gelatin, casein, starch, cationic starch, gum arabic, natural resins such as alginic soda, carboxymethyl cellulose, and hydroxyl. Ethylcellulose, polyamide, polyacrylamide, polyethyleneimine, polyvinylpyrrolidone, quaternized polyvinylpyrrolidone, polyvinylpyricillium halide, melamine resin, phenolic resin, alkyd resin,
Synthetic resins such as polyurethane, polyvinyl alcohol, ion-modified polyvinyl alcohol, polyester, and sodium polyacrylate, preferably wood-philic polymers made by crosslinking these polymers to make them water-insoluble; Examples include a woody and water-insoluble polymer complex, a woody and water-insoluble polymer having a woody segment, and the like.

As a method for forming an ink retaining layer and an ink transport layer on the top of Omura, a coating solution is prepared by dissolving or dispersing the materials preferably mentioned in "-2" in an appropriate solvent, and the coating solution is mixed with, for example, , roll coating method.

Rod bar coating method, spray coating method,
It is preferable to apply the coating on Omurakami using a known method such as the air knife coating method and dry it quickly.
The above-mentioned material may be hot-melt coated, or a single sheet may be formed from the above-mentioned material, and the sheet may be laminated onto a base material.

However, when providing an ink retention layer on Omura.

For example, it is preferable to strengthen the adhesion between the base material and the ink retaining layer by forming an anchor coat layer or the like to eliminate spaces.

If a space exists between the base material and the ink retaining layer, the surface of the recorded image will reflect diffusely, which will substantially lower the optical density of the image, which is not preferable.

Means for recording images using the recording material of the present invention include fountain pens, ballpoint pens, and felt-tip pens.

Examples include recording instruments and recording devices that use ink containing a recording agent, such as pen plotters, ink misters, ink jets, and various types of printing.

From the viewpoint of high-speed image recording, inkjet recording devices and pen plotters are suitable.

The ink used in the recording method of the present invention can be a conventionally known water-based and/or pongee thread ink, but in order to quickly penetrate the ink transport layer and be quickly absorbed and captured by the ink retention layer, Ink viscosity is 500cp
It is necessary that the value is less than or equal to s. Preferably, the viscosity is 1
00 cps or less, preferably 50 cps or less.

In addition, water-based inks are preferable in consideration of safety against fire and stain resistance against the environment.

As the recording agent contained in the ink, conventionally known coloring agents such as dyes and pigments and/or materials having color-forming properties can be used.For example, recording agents used in inkjet recording include direct dyes, basic dyes, etc. Water-soluble dyes such as , reactive dyes, and food colorings are preferred.

In the recording method of the present invention, when printing one character, since the recording surface and the viewing surface are in a front-back relationship.

Unlike conventional methods, it is necessary to use a device that can print mirror letters. However, in the recording material of the present invention, the ink transport layer can be made transparent by heating after recording, and in such a case, the recording surface can also be used as an observation surface. Therefore, in such a case, characters etc. may be recorded in a normal state.

(Examples) Hereinafter, the present invention will be specifically described based on Examples. In addition, unless otherwise specified, % or department is used in the text! i quantity standard.

Example 1 Using a polyethylene terephthalate film (thickness loOgm, manufactured by Toshi) as a translucent base material, the following composition A was coated on a piece of Omurakami using a bar coater method so that the dry film thickness was 8#Lm. and dried in a drying oven at 120°C for 5 minutes.

88 parts of Benikō 1 polyvinyl pyrrolido (PVPK-FJO, manufactured by GaP, 10% DMF solution) Novolac type phenol resin (Regitop PSK-23
20, Gunei Chemical Co., Ltd. 10%, DMF solution) 12 parts Furthermore, the following components (a), (b) and (C) were added to the bar in various blending ratios so that the dry film thickness was 204 m. It was coated by a coater method and dried in a drying oven at 90° C. for 10 minutes to obtain nine types of white opaque recording materials (one of which was a comparative example).

Polyethylene resin (W-100, manufactured by Mitsui Petrochemical Industries, Ltd.)
Solid content: 40%) Ethylene-vinyl acetate copolymer resin (Chemipearl V-10
0. Sodium dioctyl sulfosuccinate (Perex op-p, manufactured by Kako) 1 Company record 11 Component a / Component b Component c = 115 / (manufactured by Mitsui Petrochemical Industries, Ltd., solid content 40%) total of 0
．． 2 pieces) 1 company g1λ component a/component b component c=l/3/(0 of the sum of a and b
．． 8) 1 company H top J component a/component b component c=l/l/(0 of the sum of a and b
, 22) 1 proof R■'' component a/component b component c = 3/1/(0 of the sum of a and b
．． 2K) 1 company weight 1 component a/component b + component c = 10/1/ (0.2% of the total of a and b) 1 company momme J component a/component b ratio 1 & min c = 20/1/ (0.2% of the total of a and b) 1 Plates 11 Component a/component b component c = 30/l/(o, 2% of the total of a and b) 1 Ingredient U component a/component b Component c = 50/1/(0.2$ of the total of a and b) 1 melon 1u (comparative example) Component a/component b component c = 100/l/(02% of the total of a and b) Example 2 and Comparative Example The following four types of ink were used on the recording materials of the above Example and Comparative Example, and bubbles were generated with a heating resistor, and the ink was ejected using the pressure generated. Solid inkjet recording was performed using a recording apparatus having a demand-type inkjet I recording head. The compositions of the four types of inks used are shown below, and the recorded matter thus obtained was tested and evaluated in accordance with the following method to determine whether they were sufficiently suitable for the purpose of the present invention.

The evaluation results are shown in Table 1 below.

Left Elle (Composition) C, 1, Acid Yellow 23 2 parts diethylene glycol 15 parts water
85 parts Licozl (composition) C, 1, Acid Red 92 2 parts diethylene glycol 15 parts water
85 parts and U (composition) C, 1, Direct Blue 86 2 parts diethylene glycol 15 parts water
85 parts 1 ether (composition) C, 1, Direct Black 19 2 parts diethylene glycol 15 parts water
85 parts (1) Ink absorbency is
After inkjet recording, the recorded matter was left at room temperature, and the time required for the ink to sufficiently dry and fix without adhering to the finger even when the recorded area was touched with a finger was measured.

(2) The image optical density (0,0,) is the Macbeth densitometer T
Image observation side A for black ink recording area using R524
and measured from recording surface B.

(3) Coating film strength is determined by rubbing the ink transport layer surface of the recording material after drying 10 times with a plastic eraser. If there is no abnormality on the layer, rub it 0.15 times. If there is no abnormality on the layer, Δ, 5.
Those in which abnormality was observed after rubbing less than once were marked as ×.

The above results are shown in Table 1.

(Effects) With the recording material of the present invention configured as described above, it is not impossible to observe the recorded image from the side recorded with ink, like ordinary paper, but it is possible to observe the recorded image from the side recorded with ink. By observing the recorded image from the opposite side, that is, the ink-retaining layer or substrate side.

It has excellent effects that could not be obtained conventionally.

That is, since the ink retaining layer has translucency,
Diffuse reflection on the image viewing surface is reduced, and a high image optical density that cannot be achieved when recording with ink on a porous sheet such as paper can be obtained.

In addition, by adjusting the proportion of particles and binder used in the ink transport layer that serves as the recording surface, it has an appropriate film strength and contains cracks and communicating pores with an appropriate porosity. The liquid permeability of the ink transport layer is suitably controlled, and it is possible to provide an image with excellent ink absorption, recorded image density, sharpness, resolution, color quality, etc.

Furthermore, when a transparent base material is used as the base material, in addition to the above-mentioned effects based on the light transmittance of the X material, the recorded image has gloss, water resistance, weather resistance, and abrasion resistance. Granted.

The recording material of the present invention is significantly superior to the conventional method of laminating a transparent film on the surface of the recorded image in terms of the optical density of the recorded image and the operability when creating the recorded image. .

(Margin below) Heiryo Tane 1n original (spontaneous) Showa si < pto month 7th

Claims (11)

[Claims] (1) A recording material having an ink transport layer and an ink retention layer, wherein the ink transport layer is mainly composed of particles that are non-stainable to the recording material and a binder, A recording material having a weight ratio of 1/3 to 50/1 with respect to a binder. (2) The recording material according to claim (1), wherein the ink transport layer and the ink retention layer are laminated on a base material. (3) The recording material according to claim (2), wherein the base material is translucent. (4) Claim No. 2, wherein the ink transport layer is porous (
The recording material described in item 1). (5) The recording material according to claim (1), wherein the ink retaining layer is non-porous. (6) The recording material according to claim (1), wherein the ink retaining layer is mainly composed of a water-soluble or hydrophilic polymer. (7) The ink transport layer is light-diffusing, and the ink-retaining layer is more light-transmissive than the ink transport layer.
The recording material described in item 1). (8) The recording material according to claim (1), wherein the ink retaining layer has a stronger ink absorption ability than the ink transport layer. (9) The recording material according to claim (1), wherein the ink transport layer has communication holes. (10) The recording material according to claim (1), wherein the ink transport layer includes cracks. (11) A recording method in which recording is performed using ink on the recording surface of a recording material having an ink transport layer and an ink retention layer, the ink transport layer being non-stainable to the recording material. A recording method mainly composed of particles and a binder, characterized in that the weight ratio of the particles to the binder is in the range of 1/3 to 50/1.