JPS62222885A - Recording material - Google Patents

Abstract

PURPOSE:To obtain a recording image having excellent ink absorbability, a fixing property and high optical density and excellent in hue, color developability and resolving power, by providing a porous ink pervious layer and a unporous ink holding layer, and containing a undyeable particle with a particle size of 0.2-95mum in the ink pervious layer. CONSTITUTION:Because recording is performed on an ink pervious layer being a recording side by a recording liquid and a recording image is observed from an ink holding layer being an observation side, it is necessary that the ink pervious layer has high affinity to the liquid medium in the recording liquid and low affinity to a recording agent while, because the ink holding layer absorbs and catches the recording liquid temporarily absorbed by the ink pervi ous layer, it is necessary that absorbing force to the recording liquid is stronger than that of the ink pervious layer and the affinity to the recording agent is high. As the undyeable particle constituting the ink pervious layer, a thermo plastic or thermosetting org. resin particle is used and the particle size thereof is pref. 0.4-0.8mum. A binder is the one for bonding particles to each other or the ink holding layer and a known one nonabsorbable with respect to particles and the recording agent is available.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to Fell pens, fountain pens, pen plotters,
The present invention relates to a recording material suitable for a recording method using a recording liquid such as an inkjet recording device, and particularly to a recording material suitable for high-quality recording with excellent recording liquid absorption and resolution of a recorded image.

[Conventional technology]

Conventionally, recording methods using recording liquid, such as felt-tip pens,
Recording materials used for writing with a fountain pen or ballpoint pen, or for recording with a pen plotter or inkjet recording device include general paper such as high-quality paper, pound paper, and writing paper, and coated paper such as art paper and cast coated paper. Can be mentioned.

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

In other words, because high-speed recording and multicolor recording are performed that are incomparable to conventional recording materials, conventional recording materials have poor absorption of recording liquid, color development when multiple recording liquids are attached to the same location, Color properties, etc. have not reached a satisfactory level.

In order to solve these problems, coated papers such as inkjet paper having a porous ink absorbing layer on the surface of the base material have been devised.

For example, JP-A-58-136480 describes an inkjet recording medium in which an ink-receiving layer mainly composed of a pigment having a refractive index of 1.58 or less is provided on a support.

Unlike conventional recording media, this recording medium allows the recorded image to be observed from the support side, and the ink-receiving layer adjacent to the support is made of a pigment with a refractive index of 1.58 or less. By configuring it as such, it is intended to obtain a recorded image with good color reproducibility and color depth IW.

However, although this recording medium has relatively good ink absorbency, since the pigment layer is used as an ink absorbing and retaining layer, the ink does not absorb much of the ink. It has drawbacks such as poor adhesion, poor resolution of recorded images, color properties, and optical density.

In addition, recently, as the speed and quality of recording using inkjet recording devices, pen plotters, etc. has increased,
Recording materials are also required to have dramatic recording performance.

In other words, there is a need for a recording material that is significantly superior to conventional recording materials in all aspects of recording performance, such as absorption of the recording liquid, color development of the recording agent, quality of the recorded image, resolution, color, density of the recorded image, and gloss. It's here.

[Problem that the invention seeks to solve]

However, the current situation is that a recording material that simultaneously satisfies all of these recording properties has not yet been obtained.

Therefore, an object of the present invention is to provide a recording material that has excellent ink absorption and fixing properties.

Another object of the present invention is to provide a recording material from which recorded images with high optical density and excellent color properties, color development, and resolution can be obtained.

A further object of the present invention is to have a glossy surface, water resistance,
The object of the present invention is to provide a recording material from which recorded images with excellent durability such as light resistance can be obtained.

[Means for solving problems]

The above object is achieved by the present invention as follows.

That is, the present invention has a porous ink-permeable layer and a non-porous ink-retaining layer, and the ink-permeable layer has a particle size of 0.
．． 48 fi containing 2 to 95 gm of non-staining particles
The recording material is denoted by t.

[Effect]

The first feature of the recording material of the present invention is that, unlike conventional recording materials in which the image recording surface and the observation surface are the same, the image recording surface and the observation surface are in a front-back relationship, Second, the ink permeable layer contains particles that are non-stainable to the recording material and have a particle size of 0.2 to 95 gm.

That is, in the recording material of the present invention, recording is performed using a recording liquid on the ink permeable layer on the recording side, and the recorded image is observed from the ink retaining layer (or base material) on the observation side.

Therefore, the ink permeable layer has liquid permeability and has the function of quickly absorbing and transmitting the recording liquid attached to its surface.
On the other hand, the ink retaining layer has a function of absorbing and retaining the recording liquid or recording agent transferred from the ink permeable layer.

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

Therefore, the ink permeable layer wets the recording liquid medium.
It has properties such as penetration and diffusion, and has adsorption and adsorption properties for recording media.
It must be constructed of a material that does not have characteristics such as penetration and reaction.

If the ink permeable layer does not have properties such as wetting, permeation, and diffusion with respect to the recording liquid medium, when the recording liquid is applied to the surface of the ink permeable layer, it will quickly permeate inside the ink permeable layer. As a result, the absorbency of the recording liquid decreases.

Furthermore, the recording liquid remains retained in the ink permeable layer and does not reach the ink retaining layer, making it impossible to obtain a recorded image with excellent water resistance.

Furthermore, if the ink permeable layer has properties such as adsorption, penetration, and reaction with respect to the recording agent, the recording agent will remain on the surface or inside the ink permeable layer and will not reach the ink retaining layer. It becomes impossible to obtain a recorded image with high optical density and sufficient color properties.

On the other hand, the ink retaining layer is only temporarily an ink permeable layer.

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

As a result of extensive research, the present inventors have found that in the recording material having an ink-transmissive layer and an ink-retaining layer, the absorbency and permeability of the recording liquid are mainly the same as those of the ink-transmissive layer. In order to form a high quality image with good ink absorbency, the particle size of the non-staining particles constituting the ink permeable layer must be 0. 2-0.9
They discovered that it is necessary to have a range of 5 gm, leading to the present invention.

Hereinafter, the present invention will be described in detail based on embodiments.

The recording material of the present invention includes a base material as a support, an ink retention layer formed on the support 1- that absorbs and captures the recording liquid or recording agent, and an ink retention layer formed on the ink retention layer 1-. The ink permeable layer directly receives the recorded recording liquid, but has liquid permeability that does not substantially leave the recording agent behind.

However, if the ink permeable layer or the ink retaining 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, such as polyester resin, diacetate resin, triacetate resin, polystyrene resin, polyethylene resin, polycarbonate-1 resin, polymethacrylate resin, cellophane, celluloid. Examples include plastic films, plates, and glass plates made of polyvinyl chloride resin, polyimide resin, polysulfone resin, and the like.

As mentioned above, since the recording material of the present invention is to be observed from the side opposite to the recording surface, 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,
It is possible to give the base material a desired pattern or luster (moderate gloss or silky texture).

Furthermore, by selecting a base material having water resistance, abrasion resistance, and blocking resistance, it is possible to impart water resistance, abrasion resistance, and blocking resistance to the image observation surface of the recording material.

The ink permeable layer constituting the recording material of the present invention needs to have liquid permeability.

In the present invention, "d-liquid permeability" means that the recording liquid can pass through quickly;
This is a property that substantially prevents the recording agent in the recording liquid from remaining in the ink permeable layer.

In the present invention, a preferable embodiment for improving liquid permeability is that cracks and communication holes are formed on the surface and inside of the ink permeable layer.
The aim is to create a porous structure containing microscopic particles (including micro-sized ones).

For example, when recording using water-based ink, the following aspects may be mentioned.

(1) An embodiment in which the layer is made up of non-staining particles and a binder and has cracks inside; (2) The layer is made porous by dispersing other materials in the coating and treating it with a solvent. (3) A mode in which the resin is decomposed into a mixed solvent and the high boiling point solvent acts as a poor solvent for the resin and makes the inside of the layer porous; (4) A mode in which a foaming material is included during film formation. , an embodiment in which the inside of the layer is porous.

The monthly dyes used at this time are selected to be non-swellable to water and the solvent in the ink, and non-stainable to the dye in the ink.

A preferred embodiment of the ink permeable layer according to the present invention that satisfies the above-mentioned properties is, for example, an embodiment consisting of particles that do not stain the recording agent and a binder.

Examples of non-staining particles that satisfy the above properties include particles of organic resins such as thermoplastic resins and thermosetting resins, such as polyethylene, polymethacrylate-I, elastomers, ethylene-vinyl acetate polymers, styrene-acrylics, etc. polymer,
At least one of organic resin powders and emulsions such as polyester, polyacrylic, and polyvinyl ether may be used as desired.

These non-staining particles have a particle size of 0.2 to 95 m.
, more preferably one with a diameter of 0.4 to 0.8 m is selected and used.

When the particle size is smaller than 0.2 μm, the transparency of the ink permeable layer becomes high and the absorbency of the recording liquid decreases, making it impossible to obtain an image with excellent optical density and color sharpness.

When the particle size is larger than 95 gm, the ink retaining layer contains a large amount of l-
Since a large amount of ink is applied, the image dots bleed due to a decrease in ink absorption speed, resulting in a decrease in image brightness and resolution due to color mixing with adjacent dots.

The binder used in the present invention has the function of binding the particles and/or the ink retaining layer, and like the particles, it must be non-adsorbent to the recording material. be.

Preferred materials for the binder include any conventionally known materials having the above-mentioned functions, such as polyvinyl alcohol, acrylic resin, styrene-acrylic copolymer, ethylene-vinyl acetate polymer, starch,
Polyvinyl butyral, gelatin, casein, ionomer, gum arabic, carboxymethylcellulose, polyvinylpyrrolidone, polyacrylamide, phenol, melamine, epoxy, styrene/butadiene, rubber, urea, alpha-olefin, vinylurethane, polyurethane, nitrile rubber, chloroprene One or more of these resins may be used as desired.

Further, particles having a high refractive index, such as pigment particles, can be added to the ink permeable layer to the extent that the ink permeability thereof is not hindered.

Furthermore, in order to improve the function as an ink permeable layer, various additives such as surfactants, penetrants, etc. may be added to the ink permeable layer as necessary.

The content of non-staining particles in the ink permeable layer is 2
5 to 95% by weight is preferred, preferably 50 to 90% by weight
It is.

If this content is less than 25% by weight, the cracks and communication pores in the ink permeable layer will become smaller and the recording liquid absorption effect will decrease. Furthermore, if the acid content is 95% by weight or more, the adhesion between the particles or between the particles and the ink retaining layer is insufficient, making it impossible to form an ink permeable layer.

The thickness of the ink permeable layer depends on the amount of recording liquid, but is preferably 1 to 200 pLm, more preferably 5 to 1 pLm.
00gm.

Next, the non-porous ink retaining layer that substantially captures the recording liquid or recording agent absorbs and captures the recording agent that has passed through the ink permeable layer, and substantially permanently retains the recording agent. Therefore, the ink retaining layer is required to have a stronger ability to absorb recording liquid than the ink permeable layer.

This is because if the absorption power of the ink retention layer is weaker than the absorption power of the ink transmission layer, the recording liquid applied to the surface of the ink transmission layer will pass through the ink transmission layer, and the leading edge of the recording liquid will pass through the ink transmission layer. When the recording liquid reaches the holding layer, the recording liquid stays in the ink permeable layer, and at the interface between the ink permeable layer and the ink holding layer, the recording liquid permeates and diffuses laterally within the ink permeable layer. becomes.

As a result, the resolution of the recorded image decreases, making it impossible to form a high-quality image.

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

The ink retaining layer that satisfies the requirements in item 1- is preferably made of a light-transparent resin that adsorbs the recording agent and/or a light-transparent resin that is soluble and swellable in the recording liquid.

For example, acid as a recording agent? When an aqueous recording liquid containing one dye or a direct dye is used, the ink retaining layer is made of a cationic resin that has an adsorption property for the dye and/or a wood-philic polymer that has a swelling property for the aqueous recording liquid. It will be configured.

As the above-mentioned polymer, for example, those exemplified below are preferably used.

(1) Block copolymers or graft copolymers having a hydrophilic segment and a hydrophobic segment in the molecule These block copolymers or graft copolymers are generally water-insoluble but hydrophilic. The wood-philic segments of such polymers include, for example, carboxyl groups, sulfonic acid groups, hydroxyl groups, ether groups, acid amide groups, methylolated groups thereof, primary to tertiary amine groups, quaternary ammonium groups, etc. Bee with a woody group of:
A segment in which two or more Jlz monomers are polymerized, and examples of such hydrophilic monomers include (meth)
Mono (meth)acrylate or monomaleate of polyols such as acrylic acid, maleic anhydride, vinyl sulfonic acid, sulfonated styrene, vinyl acetate), ethylene glycol, (meth)acrylic amide, methylolated products thereof, mono- or dialkylamine ethyl Examples include (meth)acrylates, quaternized products thereof, vinylpyrrolidone, vinylpyridine, and the like.

Hydrophobic polymer segments include olefins such as ethylene, propylene, and butylene; aromatic vinyl compounds such as styrene, methylstyrene, and vinylnaphthalene; halogenated olefins such as vinyl chloride, vinylidene chloride, and vinylidene fluoride; It is a polymer of two or more heptamers such as acrylic acid, crotonic acid, and various alcohol esters of low unsaturated carboxylic acids.

In addition, water-soluble polymers other than those mentioned above, such as albumin,
Gelatin, casein, starch, cationic starch, gum arabic, natural resins such as alginate sorta, polyvinyl alcohol, polythemide, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polyvinylpyricillium halide, melamine resin, polyurethane, polyester, polyacrylic acid soda It goes without saying that hydrophilic natural or synthetic polymers such as E.g. These crosslinked polymers are crosslinked with a suitable crosslinking agent or radiation to such an extent that they become water-insoluble without losing their wood-philic properties.

(3) Polymer complex A polymer complex is composed of two or more types of water-soluble to hydrophilic polymers that have different phase buds and that interact with each other, producing a mixture with properties different from any of the original polymers. For example, two or more types of polymers form some kind of strong bond due to interionic electrostatic force, hydrogen bonding, van der Waals force, partial transfer of charge, etc.

Although various kinds of polymer complexes can be used, a particularly preferred one in the present invention is a polymer complex consisting of a basic polymer and an acidic polymer.

Note that the material constituting the ink retaining layer is not particularly limited as long as it has the function of absorbing and trapping the recording liquid and can form a non-porous layer.

The thickness of the ink holding layer may be sufficient as long as it is sufficient to absorb and trap the recording liquid, and although it varies depending on the amount of recording liquid, it is preferably 1 to 50 gm, more preferably 5 to 1100 gm.
It is pL.

As a method for forming an ink retaining layer and an ink permeable layer on Kanmura, a 4-liquid solution is prepared by dissolving or dispersing it in a suitable solvent as shown in L, and the coating solution is applied, for example, by a roll coach ink method, It is preferable to apply the coating onto Kanmura by a known method such as a rod par coating method, a spray coating method, an air knife coating method, etc., and then quickly dry it. A method may also be used in which a sheet is formed and the sheet is laminated onto a base material.

However, when providing the ink retaining layer on the base material 2, it is necessary to ensure strong adhesion between the base material and the ink retaining layer and eliminate spaces.

If a space exists between the base material and the ink retaining layer, the surface of the recorded image will be subject to diffuse reflection, which will reduce the substantial optical density of the image, which is not preferable.

Examples of means for forming an image using the recording material of the present invention include a fountain pen, a ballpoint pen, a felt-tip pen, and a pen block.
, Inkmiss I, inkjet, various types of printing, and other recording instruments and recording apparatuses that use a recording liquid containing a recording agent.

Among these recording devices and recording devices, inkjet recording devices and pen blocks are preferred from the viewpoint of high-speed image recording.

The recording liquid for recording on the recording material of the present invention includes:
Conventionally known aqueous and/or pongee yarn recording liquids are preferred, and in order to quickly penetrate the ink permeable layer and be quickly absorbed and captured by the ink retaining layer, the recording liquid should have a viscosity of 1000c.
ps or less, preferably 100 cps or less, preferably 50 cps or less
It is necessary that it is less than cps.

Further, in consideration of stability against fire, resistance to environmental contamination, etc., a water-based recording liquid is preferable. As the recording agent contained in the recording liquid, any conventionally known coloring agents such as dyes and pigments and/or those having color-developing properties can be used.

For example, as the recording agent used in inkjet recording, water-soluble dyes such as direct dyes, acid dyes, basic dyes, reactive dyes, and food colorings are preferred.

Formation of an image using the recording material of the present invention is carried out by recording an image with a recording liquid on the ink-permeable layer side of the recording material using a recording device capable of printing mirror characters (reverse characters). .

[Implementation Moe]

Hereinafter, the present invention will be specifically explained based on Examples. still,
In the text, parts are by weight unless otherwise specified.

Examples and Comparative Examples A polyethylene terephthalate film (thickness 100 gm + manufactured by Toshi) was used as a translucent base material, and the following composition A was coated on the film using a bar coater method so that the dry film thickness was 8 μm. and dried in a drying oven at 120°C for 5 minutes.

Composition A was further coated with the following compositions B-F under the following conditions using a bar coater method, and dried in a drying oven to obtain recording material 1.
~6 was created.

Composition B (Dried film thickness 5 pm, dried at 90°C for 8 minutes) Composition B (Dried film thickness 1100 pL, dried at 80°C for 20 minutes) Composition D (Dried film thickness 1100 pL, dried at 80°C for 20 minutes) Material 3) Dry film thickness: 100 #Lm, 80° Cl2O min ■ 1 drying > Composition E Material 5) Dry film thickness: 100 m, dried at 80° C. for 20 minutes Composition G (Kai Kaizai 6) The recording materials 1 to 6 thus obtained were all white opaque. It was something.

For these recording materials, we use a recording device with an on-demand inkjet recording head that uses the following four types of ink to generate bubbles with a heat-generating resistor and uses the pressure to eject recording liquid. Inkjet recording was performed in solid color.

Table 1 shows the compositions of the four types of recording liquids used.

Table 1 Yellow ink C, 1, Direct Yellow 86
2parts N-methyl-2-pyrrolidone
10 parts diethylene glycol
20 parts polyethylene glycol #200 15m
water
55 parts magenta ink C, 1, acid red 35
2parts N-methyl-2-pyrrolidone
10 parts diethylene glycol
20 parts polyethylene glycol #200 15 parts water
55 parts cyan ink C, 1, direct blue 86
2parts N-methyl-2-pyrrolidone
10 parts diethylene glycol
20 parts polyethylene glycol #200 15 parts water
55 parts black ink C, 1, food black 2
2parts N-methyl-2-pyrrolidone
10 parts diethylene glycol
20 parts polyethylene glycol #200 15 parts water

55 copies of the records obtained in this way,
It was tested and evaluated in accordance with the following method to determine whether it was sufficiently suitable for the purpose of the present invention.

(2) Ink absorption was measured by leaving the recorded matter at room temperature after inkjet recording, and measuring the time until the ink was sufficiently dried and fixed without adhering to the recorded area even when touched with a finger.

2) Image optical density (0, D) is determined by Macbeth densitometer TR-
524, image observation surface A for the black ink recording area.
was measured from recording surface B.

3) To determine the dot shape, observe the printed dots with a stereomicroscope. If the dot is slightly round, mark it as 0. If the circle is slightly distorted, mark it as △.
Irregular shapes were marked as ×.

4) The degree of bleeding was measured by measuring the printed dots using a stereomicroscope, and was expressed by how many times larger the printed dots were than the ink droplets.

5) Color vividness was compared by visual inspection of the colors of the inkjet recorded images, and the best one was ranked as 0, the worst as ×, and ranked as ■, 0, Δ, and ×.

Table 2 [Effects of the Invention] As shown in 2 below, in the recording material of the present invention, the recording surface and the observation surface are in a front-back relationship, that is, recording is performed from the ink-permeable layer side, and the recording material is By observing from the holding layer side), it has an extremely high optical density, which was previously impossible when recording on a porous sheet such as paper.
It can provide clear recorded images.

Furthermore, the recording material of the present invention is excellent in that it satisfies both ink absorbency and the resolution of a recorded image, since the ink permeable layer contains particles of appropriate particle size.

Claims (5)

[Claims] (1) It has a porous ink-permeable layer and a non-porous ink-retaining layer, and the ink-permeable layer contains particles that are non-stainable to the recording material with a particle size of 0.2 to 95 μm. Characteristic recording material. (2) The recording material according to claim 1, wherein the ink retaining layer and the ink permeable layer are laminated on a base material. (3) The recording material according to claim 2, wherein the base material is translucent. (4) Claim 1, wherein the ink retaining layer is mainly composed of a cationic resin and/or a hydrophilic polymer.
Recording material described in section. (5) The recording material according to claim 1, wherein the non-stainable particles are resin particles.