JPS62282965A - Recording method - Google Patents

Abstract

PURPOSE:To enhance ink absorbability and ink fixability, by performing recording on a material to be recorded having an ink transport layer and an ink holding layer using a recording liquid under such a condition that the thickness of the ink holding layer and the diameter of the recording droplet satisfy specific relation. CONSTITUTION:An ink holding layer substantially absorbing and catching a recording liquid or a recording agent is provided on a base material and, further, an ink transport layer directly receiving the recording liquid but having a liquid passing property substantially leaving no recording agent is laminated thereto to form a material to be recorded. Recording is performed on said material to be recorded using the recording liquid so that the thickness A(mum) of the ink holding layer and the diameter D(mum) of the recording liquid droplet satisfy the relation shown by a specific formula. By this method, a recording image having high optical density and excellent in hue, a color forming property and resolving power is obtained.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a recording method using a recording liquid such as a felt pen, a fountain pen, a pen plotter, an ink jet recording device, etc., and particularly relates to a recording method using a recording liquid. The present invention relates to a recording method for obtaining high-quality images with excellent liquid absorption, color properties, and optical density.

[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 mainly of pigments with a refractive index of 1.58 or less. By configuring it as such, it is possible to obtain a recorded image with good color reproducibility and color density.

However, although this recording medium has relatively good ink absorption, since the pigment layer is used as an ink absorption/retention layer,
It has drawbacks such as poor ink fixability and poor resolution, color, and optical density of recorded images.

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 and a recording method that simultaneously satisfy all of these recording characteristics have not yet been obtained.

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

Another object of the present invention is to provide a recording method that allows recording images with high optical density (and excellent color properties, color development, and resolution) to be obtained.

A further object of the present invention is to provide a recording method by which a recorded image having a glossy surface and excellent durability such as water resistance and 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 is a method for recording using a recording liquid on a recording material having an ink transport layer and an ink retention layer, the method comprising:
This recording method is characterized in that the thickness A (μm) of the ink retaining layer of the recording material and the diameter D (μm) of the recording droplet satisfy the following formula.

-< A/D < 10 [Function] The recording method of the present invention is characterized by performing recording with a recording liquid on the ink transport layer, which is the ink applying side, and retaining the recording liquid (particularly the recording agent) in the ink holding layer. A recorded image is formed by using a recording material having an ink retaining layer having a suitable layer thickness depending on the diameter of the ink droplet.

Therefore, the ink transport layer has liquid permeability and has the function of quickly absorbing and transmitting the recording liquid attached to its surface, while the ink retaining layer has liquid permeability that allows the recording liquid that has migrated from the ink transport layer to pass through the ink transport layer. Alternatively, it has a function of absorbing and retaining a recording agent.

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

Therefore, the ink transport layer wets and 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 by selecting a material that does not have characteristics such as penetration and reaction.

If the ink transport 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 transport layer, it will quickly penetrate into the inside of the ink transport layer. As a result, the absorbency of the recording liquid decreases.

Furthermore, the recording liquid remains retained within the ink transport 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 transport 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 transport layer and will not reach the ink holding layer. It becomes impossible to obtain a recorded image with high optical density and sufficient color properties.

On the other hand, since the ink retaining layer absorbs and captures the recording liquid temporarily absorbed by the ink transport layer, it must have a stronger ability to absorb the recording liquid than the ink transport 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 intensive research, the present inventors found that in the recording material having the above-mentioned ink retention layer and ink transport layer, the absorption capacity of the recording liquid largely depends on the thickness of the ink retention layer, and high quality images can be formed. In order to achieve this, it was found that it was necessary to adjust the layer thickness of the ink retaining layer of the recording material used according to the diameter of the recording droplet, and this led 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, and absorbs substantially the recording liquid or recording agent formed on the support.
It consists of an ink retaining layer that captures the ink, and an ink transport layer formed on the ink retaining layer that directly receives the recording liquid but has liquid permeability that does not substantially leave the recording agent behind.

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, such as polyester resin, diacetate resin, triacetate resin, polystyrene resin, polyethylene resin, polycarbonate resin, polymethacrylate resin, cellophane, celluloid, polychloride resin, etc. vinyl resin,
Examples include plastic films, plates, and glass plates made of polyimide resin, polysulfone resin, and the like.

In addition, in the recording material of the present invention, when observing a recorded image from the side opposite to the ink-applied 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 ultimately has translucency (for example,
It is possible to give the base material a desired pattern or luster (moderate gloss or grain pattern).

Furthermore, by selecting a base material having water resistance, abrasion resistance, and blocking resistance, water resistance, abrasion resistance, and blocking resistance can be imparted to the image observation surface of the recording material.

The ink transport layer constituting the recording material of the present invention needs to have 1 liquid permeability.

The term "liquid permeability" as used in the present invention refers to the property of allowing the recording liquid to pass quickly through the ink transport layer and not substantially leaving the recording agent in the recording liquid in the ink transport layer.

In the present invention, a preferable embodiment for improving liquid permeability is to have cracks and communication holes on the surface and inside of the ink transport 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 composed of non-porous particles and a binder and has internal cracks; (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 dispersed in 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 foamable material is included during film formation; A mode in which the inside of the layer is porous.

The materials 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 transport layer according to the present invention that satisfies the above properties is, for example, an embodiment consisting of particles that are non-stainable to the recording agent and a binder.

Particles satisfying the above properties include organic resin particles such as thermoplastic resins and thermosetting resins, such as monolithic polyethylene, polymethacrylate, elastomers, ethylene-vinyl acetate copolymers, styrene-acrylic copolymers, and polyesters. , organic resin powders and emulsions such as polyacrylic and polyvinyl ether, and powders of inorganic pigments treated to make them non-porous.

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

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 1, carboxymethyl cellulose,
Polyvinylpyrrolidone, polyacrylamide, phenol, melamine, epochino, styrene-butadiene rubber,
One or more resins such as urea, α-olefin, chloroprene, nitrile rubber, vinyl urethane, and polyurethane may be used as desired.

Furthermore, in order to improve the function as an ink transport layer, various additives such as plasticizers,
Ultraviolet absorbers, antioxidants, anti-piping agents, anti-aging agents, fluorescent whitening agents, colorants, surfactants, penetrants, etc. may be added to the ink transport layer.

Furthermore, conventionally known pigment particles may be added to the extent that they do not impede the liquid permeability of the ink transport layer.

The mixing ratio (weight ratio) of the particles and the binder is preferably in the range of particles/binder = 1/3 to 50/1, more preferably in the range of 3/1 to 20/1. .

When this mixing ratio is 1/3 or less, cracks and communication pores in the ink transport layer become small, and the recording liquid absorption effect decreases. Furthermore, if the mixing ratio is 50/1 or more, the adhesion between the particles or between the particles and the ink retaining layer becomes insufficient, making it impossible to form an ink transport layer.

The thickness of the ink transport layer depends on the amount of recording liquid, but is preferably 1 to 200 μm, more preferably 5 to 10 μm.
It is 0 μm.

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

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

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

Furthermore, as described above, when observing a recorded image from the side opposite to the ink-applied surface, the ink-retaining layer needs to be light-transmissive.

The ink retaining layer that satisfies the above requirements is preferably composed 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, when an aqueous recording liquid containing an acid dye or a direct dye is used as a recording agent, the ink retaining layer has a cationic resin that has an adsorption property for the dye and/or a swellability for the aqueous recording liquid. It will be composed of a hydrophilic polymer.

As the above-mentioned polymer, those illustrated 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. Hydrophilic 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 amino groups, quaternary ammonium groups, etc. It is a segment in which two or more vinyl monomers having hydrophilic groups are polymerized. Examples of such wood-philic monomers include (meth)acrylic acid,
Mono(meth)acrylates or monomalates of polyols such as maleic anhydride, vinyl sulfonic acid, sulfonated styrene, vinyl acetate, and ethylene glycol;
(meth)acrylic acid amide and their methylolated products,
mono- or dialkylaminoethyl (meth)acrylate,
Examples include quaternized products of these, 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 monomers such as acrylic acid, crotonic acid, and various alcohol esters of underground saturated 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 sodium alginate, polyvinyl alcohol, polyamide, polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, polyvinylpyricillium halide, melamine resin, polyurethane, polyester, sodium polyacrylate It goes without saying that hydrophilic natural or synthetic polymers such as the above or hydrophobic natural or synthetic polymers modified to be water-insoluble can also be used as the hydrophilic polymer segment or the hydrophobic polymer segment.

(2) Crosslinked water-soluble polymers Various water-soluble polymers as described above and below are crosslinked with a suitable crosslinking agent or radiation to the extent that they become water-insoluble without losing their hydrophilicity.

(3) Polymer complex A polymer complex is made up of two or more water-soluble to hydrophilic polymers that are different from each other and act on each other, and it produces 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.

Various types of such polymer complexes can be used, but particularly preferred in the present invention are polymer complexes 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 retaining layer may be sufficient as long as it absorbs and captures the recording liquid, but in order to obtain a high-quality image, it should be 1/100 to 10 times the diameter of the recording droplet, preferably 1/80 to 8 Approximately twice as much is required.

When the thickness of the ink retaining layer is 1/100 of the recording droplet diameter, the absorbency is good, but the image density is low and the color clarity is poor.

As a method for forming an ink retaining layer and an ink transport layer on a base material, a coating solution is prepared by dissolving or dispersing it in the above-mentioned appropriate solvent, and the coating solution is coated by, for example, a roll coating method,
Rod bar coating method, spray coating method,
It is preferable to apply the coating onto a substrate by a known method such as an air knife coating method and dry it quickly. A method such as laminating the sheet onto a base material may also be used.

However, when providing the ink retaining layer on the base material, 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 lower the substantial optical density of the image, which is not preferable.

Means for forming an image using the recording material of the present invention include a fountain pen, a ballpoint pen, a felt pen, a pen plotter, etc.
, ink mist, inkjet, various types of printing, and other recording devices and devices that use a recording liquid containing a recording agent.

Among these recording devices and recording devices, inkjet recording devices and pen plotters 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 oil-based recording liquids are preferred, and in order to quickly penetrate into 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 must be 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 coloring properties can be used. For example, as a recording agent used in inkjet recording, direct Water-soluble dyes such as 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 transparentizing the ink transport layer and using a normal recording device and writing instrument. Using a recording device that can print (reverse characters),
This is done by recording an image using a recording liquid on the ink transport layer side of the recording material.

〔Example〕

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 μm, manufactured by Toshi) was used as a light-transmitting base material, and the following composition A was applied onto the base material in a dry film thickness as shown in Table 2. , by a bar coater method, and dried in a drying oven at 120'C for 5 minutes.

Composition A Further, the following composition B was added on top of it to a dry film thickness of 15%.
Coated using a bar coater method to a thickness of 80 μm.
°0 Dry in a drying oven for 10 minutes, record material 1.2, 3,
I got a score of 4.5.

Composition B Furthermore, in the recording material 3, the following composition C was used instead of the composition A to obtain a recording material 6.

Further, in the recording material 3, the following composition was used instead of the composition A to obtain a recording material 7.

Composition C Composition D * All of the seven recording materials thus obtained were white and opaque.

For these recording materials, two types of on-demand type inks are used to generate bubbles using a heat-generating resistor using the four types of ink shown in Table 1, and the resulting pressure discharges the recording liquid. Solid inkjet recording was performed using a recording apparatus having an inkjet recording head.

At this time, the ink droplet diameter when using each device was 20 μm.
and 80 μm.

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

Table 1 Yellow ink c, r, Direct Yellow 86 2 parts N-methyl-2-pyrrolidone 10 parts diethylene glycol 20 parts polyethylene glycol #
200 15 parts water
55 parts Magenta Ink C,1, Acid Red 35 2 parts N-methyl-2-pyrrolidone 10 parts Diethylene glycol 20 parts Polyethylene glycol #2
00 15 parts water
55 parts Cyan ink C, 1, Direct Blue 86 2 parts N-methyl-2-pyrrolidone 10 parts diethylene glycol 20 parts Polyethylene glycol: 2
00 15 parts water
55 parts Black Ink C, 1, Food Black 2 2 parts N-methyl-2-pyrrolidone 10 parts diethylene glycol 20 parts polyethylene glycol #20
0 15 parts water
55 copies of the thus obtained recorded material was tested and evaluated in accordance with the following method to determine whether it was sufficiently suitable for the purpose of the present invention.

1) Ink absorbency was determined by measuring the time it took for the recorded matter to dry and fix sufficiently without adhering to the recorded area even when touched with a finger by leaving the recorded matter at room temperature after inkjet recording.

2) Image optical density (0, D) is determined by Macbeth densitometer TR-
524, the image observation surface (
Measured from the base material side).

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

4) The degree of bleeding is determined by measuring the printed dot using a stereomicroscope.
It is indicated by how many times the size of the ink droplets.

5) Color clarity was determined by visually comparing the color clarity of the inkjet recorded images, and ranking the best one as ◎, the worst as ×, and ranked ◎, ○, △, and ×.

Table 2 [Effects of the Invention] As described above, according to the present invention, the recording liquid and the recording material are matched, and moreover, recording is performed from the ink transport layer side, which is the ink application surface, and the image is formed from the substrate side. By observing, a recorded image with high optical density and excellent clarity can be obtained.

In addition, the ink transport layer, which is the recording surface, is made of a porous layer with liquid permeability, and the ink retention layer has a high affinity and sufficient absorption capacity for the recording liquid, so it is easy to absorb the recording liquid. The quality and resolution of recorded images are improved.

Furthermore, by using a light-transmitting base material as the base material, in addition to the above-mentioned effects based on the light-transmitting nature of the base material, gloss, water resistance, weather resistance, and abrasion resistance are imparted to the recorded image. Ru.

Claims (5)

[Claims] (1) A method of recording with a recording liquid on a recording material having an ink transport layer and an ink retention layer, the method comprising: thickness A (μm) of the ink retention layer of the recording material and recording droplet diameter D (μm) ) satisfies the following formula. 1/100<A/D<10 (2) The recording method according to claim 1, wherein the recording material comprises an ink retaining layer and an ink transport layer laminated on a base material. (3) The recording method according to claim 1, wherein the ink transport layer of the recording material is porous. (4) The recording method according to claim 1, wherein the ink transport layer of the recording material contains particles that are non-stainable to the recording agent and a binder. (5) The recording method according to claim 1, wherein the ink retaining layer of the recording material is non-porous.