JP2001115199A - Three-dimensional image forming method and three-dimensional image ink - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To form a three-dimensional image on a widely used general-purpose recording medium such as copy paper by an ink jet recording method. A three-dimensional image is formed by forming and heating a dot image on a recording medium using a three-dimensional image ink containing a coloring material and a resin which is soluble in alcohol and thermally expands.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for expanding ink by heating, which is applicable to office equipment such as printers, copiers and facsimile machines using various recording media such as paper, cloth, leather and nonwoven fabric. The present invention relates to a method of forming a three-dimensional image having a climax.

[0002]

2. Description of the Related Art In an ink discharge method called an ink jet recording method, ink such as heat, light, electric charge, and vibration is applied to an ink to discharge the ink from a discharge port.
This is adhered on a recording medium to form a dot image.
Above all, bubble jet recording, in which ink is heated more rapidly than nucleate boiling, bubbles are generated in the ink by causing film film boiling, and ink is ejected using pressure caused by the volume change generated when the bubbles are generated. The method is conventionally adopted. JP-B-61-59911-JP-B-61
-As disclosed in each publication such as 59914,
As a recording apparatus used in the bubble jet recording method, an ejection port for ejecting ink, an ink flow path communicating with the ejection port, and an energy generation means for ejecting ink arranged in the ink flow path are provided. Generally, a device mainly including a bubble generation region including a heat generating portion is generally used.

According to the bubble jet recording method, a high-quality image can be recorded at high speed and with low noise, and the ink ejection head used in this recording method has a high density of ejection ports for ejecting ink. Can be arranged. Therefore, the bubble jet recording method has an advantage that a high-resolution recorded image and a color image can be easily obtained with a small-sized recording device. For these reasons, the bubble jet recording method has been adopted in many office devices such as printers, copiers, and facsimile machines, and has also been adopted in industrial systems such as textile printing devices.

FIG. 9 schematically shows a writing process in which a dot image is formed on a recording medium by a conventional bubble jet recording method or the like. FIG. 9A schematically shows a state immediately after the ink lands on the recording medium. FIGS. 9B to 9C show a process in which the ink permeates into the recording medium. FIG. 9D schematically shows a state in which the color material in the ink is adsorbed on the fibers in the recording medium and solidifies to form a dot image.

[0005] In recent years, there has been an increasing demand for forming images composed of raised pictures and characters. As a method of forming a raised three-dimensional image on the recording medium, before the ink dries after the writing process, a thermoplastic resin powder is sprinkled on the surface of the ink and adhered to the ink, and an extra thermoplastic resin powder is applied. Then, a three-dimensional image forming method has been adopted in which the thermoplastic resin powder is melted by heating and the surface of the ink is covered with the thermoplastic resin, thereby giving rise to heat.

However, this method is troublesome, and it is difficult to uniformly adhere the thermoplastic resin powder to the ink. Therefore, the degree of swelling varies depending on the location within a single recording medium, resulting in an uneven three-dimensional image. Was sometimes formed. Further, since it is difficult to attach the same amount of thermoplastic resin powder to the ink every time, the degree of swelling may be different each time a three-dimensional image is formed.

[0007]

In the stencil printing method, the ink itself is heated (JP-A-59-1577 and JP-A-61-188475) or light (JP-A-11-105399). The above problem has been solved by dispersing the expanding microcapsules. That is, plate making is performed using a stencil sheet, and after passing an ink containing microcapsules through a perforated portion of the sheet formed by plate making to write an image on a recording medium, heat or light is applied. Then, the microcapsules are expanded to form a stereoscopic image. According to this method, it is not necessary to attach the thermoplastic resin powder after writing the image, and a three-dimensional image having a uniform unevenness can be formed only by applying heat or light to the image.

However, when the ink containing the above microcapsules is used in an ink jet recording system, the following problems are feared. In other words, in order to respond to the recent demand for finer images, the ink ejection head used in the ink jet recording system has a highly integrated structure, and the diameter of the ink flow path and the ink ejection port in the ink ejection head. Is as extremely thin as 10 to 30 μm. However, in conventional inks containing microcapsules, the microcapsules are not dissolved but dispersed only in the ink, so the microcapsules block the thin ink flow paths and ink ejection ports,
Ink ejection failure may occur. Similarly, since the microcapsules are not dissolved but dispersed in the ink, an image formed by the ink containing the microcapsules may have shading or uneven color, and the print quality may be degraded.

In order to solve the above-mentioned problems, attempts have been made to use a conventional microcapsule by a hydrophilic treatment or a dispersion treatment and use it in an ink jet recording system, but it is still insufficient.

On the other hand, in JP-A-9-207428 and JP-A-8-175029, after a foamed layer is formed in a recording medium and an image is recorded on an ink receiving layer by an ink jet recording method, heat or light is applied. There is disclosed a method of forming a three-dimensional image by foaming a foam layer by, for example, such a technique. Also, like the Braille printer TP-32 (manufactured by Toyo Hybrid Co., Ltd.) that prints Braille documents for the blind,
2. Description of the Related Art A readable swell is formed on paper by an embossing method. However, these systems require a dedicated recording medium, and cannot form a three-dimensional image on a widely spread recording medium such as copy paper by the inkjet recording method.

Therefore, despite the fact that the ink jet recording method has excellent characteristics, it is difficult to form a three-dimensional image on a widely used general-purpose recording medium such as copy paper by the ink jet recording method. Until it was difficult.

[0012]

According to the present invention, there is provided an ink jet recording method comprising:
A three-dimensional image forming method comprising: a writing step of forming a dot image made of ink in an image forming area of a recording medium; and a heating step of fixing and drying the ink on the recording medium and simultaneously thermally expanding the ink. Wherein the ink contains a coloring material and an alcohol-soluble resin that thermally expands during the heating step.

According to the present invention, there is provided a three-dimensional image comprising a coloring material and an alcohol-soluble resin which thermally expands during a heating step of fixing and drying a dot image made of ink on a recording medium. An ink for use is provided.

The resin that expands thermally in the present invention is soluble in alcohol unlike the conventionally used microcapsules and the like, and thus is dissolved instead of being dispersed in the ink. That is, the ink is dissolved well in the ink finally prepared, and no precipitation or the like occurs. Therefore, the resin that expands thermally in the present invention does not block the thin ink flow path or the ink discharge port, and the ink discharge failure does not occur. In addition, since the resin that expands in the present invention is not dispersed but dissolved in the ink, an image formed by the ink according to the present invention can achieve good print quality without shading or color unevenness. In the present invention, since it is not necessary to subject the thermally expanding resin to a hydrophilic treatment or a dispersion treatment, the preparation of the ink is simple and excellent in productivity.

The ink containing a resin which expands in the present invention is suitably used in an ink jet recording system, and a recording medium which has been conventionally used can be used. Since the resin that expands thermally in the present invention is soluble in alcohol, it can be mixed well with the ink by the same handling as the conventional additive for the ink.

By adopting the bubble jet recording method among the ink jet recording methods, it is possible to form a three-dimensional image with better quality. That is, in the present invention, the ink jet recording system generates bubbles in the ink by rapidly raising the temperature of the ink and causing film boiling, and the bubble ejecting the ink using the pressure generated when the bubbles are generated. A jet recording method may be used. Further, the bubble jet recording method includes an ejection port for ejecting the ink, a bubble generation region for generating the bubble in the ink, and an ink flow path communicating with the ejection port, A method using an ink ejection head that ejects ink by the generated pressure may be used. However, the present invention is not limited to these.

Further, in the present invention, the heating step comprises:
The recording may be performed by a heating unit disposed on the conveyance path of the recording medium. Further, the heating step may be performed by a heating unit disposed at a position facing the ink discharge head with respect to the recording medium. With such a configuration, a three-dimensional image can be formed immediately after the writing step during conveyance of the recording medium, so that the printing efficiency is further improved. However,
The present invention is not limited to these.

Further, in the present invention, the resin is preferably an alcohol-soluble nylon resin. Further, the coloring material may be a dye, a pigment, or a mixture of a dye and a pigment. Since the nylon resin has a polar group, it interacts with the recording medium and improves the fixability of the ink to the recording medium. Similarly, dyes and pigments are also preferably used as coloring materials because of their good fixability to a recording medium. However, the present invention is not limited to these.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited thereto.
FIG. 1 shows a state in which a three-dimensional image is formed after the ink applied on the recording medium by the ink ejection head lands in the present invention. FIG. 1A schematically shows a state immediately after the ink lands on the recording medium. FIG.
(B) schematically shows how the ink permeates the recording medium. FIG. 1C is a schematic diagram in which the entire recording medium or only the portion where the ink has penetrated is heated in that state. FIG. 1 schematically shows how the resin thermally expands to form a three-dimensional image.
(D).

FIG. 2 schematically shows how a three-dimensional image is formed by changing the height of the swell from the recording medium. The steps (a) to (d) are the same as those in FIG. 1, but by changing the amount of ink applied from the ink ejection head, the rise of the three-dimensional image finally formed on the recording medium is increased. Height can be changed. In order to change the ink amount, the ink ejection volume may be changed, or the application of the ink to the same area several times, such as a multi-drop, may be repeated.

Preferred examples of the resin which expands thermally in the present invention include an alcohol-soluble nylon resin. Alcohol-soluble nylon resin is a nylon resin that is easily dissolved in lower aliphatic alcohols such as methanol and ethanol by techniques such as copolymerization and modification. Easy to mix. Unlike the ordinary nylon resin, the alcohol-soluble nylon resin of the present invention is copolymerized or modified, so that the crystallinity is reduced, and the alcohol-soluble nylon resin dissolves well in alcohol and water. It is one of the suitable resins as a component of. Note that the alcohol-soluble nylon resin is well dissolved in the ink finally obtained, and precipitation does not occur.

The preferable addition amount of the alcohol-soluble nylon resin is 0.1% by mass with respect to the entire stereoscopic image ink.
Not less than 10% by mass, more preferably not less than 0.2% by mass and not more than 8% by mass. Within this range, the ink exhibits an appropriate expansion rate and the image is not destroyed.

Alcohol-soluble nylon resins can be generally classified into two types. One type is a so-called copolymer nylon obtained by copolymerizing nylon 6, nylon 66, nylon 610, nylon 11, nylon 12, and the like. One is a type called a modified nylon obtained by chemically modifying nylon, such as N-alkoxymethyl-modified nylon and N-alkoxyethyl-modified nylon, and any of them can be suitably used in the present invention.

Next, other components constituting the three-dimensional image ink used in the present invention will be specifically described.
The three-dimensional image ink according to the invention may contain water, a water-soluble organic solvent, a coloring material, and an additive in addition to the resin that expands thermally.

As the water, it is preferable to use ion-exchanged water (deionized water) instead of general water containing various ions. The content of water in the three-dimensional image ink is preferably in the range of 10% by mass to 99% by mass of the total mass of the three-dimensional image ink, and more preferably 30% by mass to 90% by mass.
The following ranges are preferred. Within this range, various characteristics of the three-dimensional image ink are more preferable.

Examples of the water-soluble organic solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol,
aliphatic alcohols having 1 to 4 carbon atoms such as sec-butyl alcohol and tert-butyl alcohol; amides such as dimethylformamide and dimethylacetamide;
Ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2, Alkylene groups such as 6-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol, etc.
Alkylene glycols containing 6 carbon atoms; glycerin; ethylene glycol monomethyl (or ethyl)
Lower alkyl ethers of polyhydric alcohols such as ether, diethylene glycol methyl (or ethyl) ether, and triethylene glycol monomethyl (or ethyl) ether; N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2- And imidazolidinone.

The content of the water-soluble organic solvent in the three-dimensional image ink of the present invention is preferably in the range of 3% by mass to 50% by mass, more preferably 3% by mass to 40% by mass of the total mass of the three-dimensional image ink. % Is preferable. Within this range, various characteristics of the three-dimensional image ink are more preferable.

The above-mentioned liquid medium can be used alone or as a mixture. An example of a preferable liquid medium composition is composed of a mixture of water and one or more water-soluble organic solvents. Polyhydric alcohols such as ethylene glycol, glycerin, 1,2,6-hexatriol, thiodiglycol, 2-
At least one water-soluble high-boiling organic solvent such as pyrrolidone
Those containing more than one kind are exemplified.

The coloring material used in the present invention may be a dye or a pigment. As the dye, a water-soluble dye can be used, and further, water, a water-soluble organic solvent and other components such as a viscosity adjuster, a pH adjuster, a preservative, a surfactant and an antioxidant are required. It is added according to.

The water-soluble dye used in the present invention includes:
There is no particular limitation as long as it is a water-soluble acid dye, direct dye, or reactive dye described in the Color Index.
In addition, there are no particular restrictions on those not described in the Color Index as long as they have an anionic group, such as a sulfone group and a carboxyl group. The dye described above is
0.1% by mass, preferably based on the total amount of the stereoscopic image ink
It may be used in the range of not less than 20% by mass and more preferably not more than 0.5% by mass and not more than 15% by mass. Within this range, the physical properties of the obtained three-dimensional image ink will be more preferable.

The pigment in the present invention may optionally contain water,
A water-soluble organic solvent, a dispersant, and other components such as a viscosity modifier, a preservative, a surfactant, and an antioxidant may be added. Here, the pigment may be of a type to which water solubility is imparted by a dispersant, or a type to which water solubility is imparted by forming a water-soluble carboxyl group or the like around the pigment particles by plasma treatment or the like. .

The pigment used in the present invention is not particularly limited, but the following are exemplified. First, in the present invention, as the pigment used for the black ink, carbon black may be mentioned. In particular, it is manufactured by the furnace method and the channel method, and has a primary particle diameter of 15 to 40 mm, which is determined by the BET method. A specific surface area of 50 to 300 m ² / g,
Those having characteristics such as a DBP refueling amount of 40 to 150 ml / 100 g, a volatile component of 0.5 to 10%, and a pH value of 2 to 9 are preferably used. As a commercially available product having such characteristics, for example, 2300, no. 90
0, MCF88, No. 40, no. 52, MA7, M
A8, No. 2200B (Mitsubishi Chemical Corporation), RA
VEN1255 (manufactured by Columbia), REGAL400
R, REGAL660R, MOGULL (above, manufactured by Cabot Corporation), Color Black FWL, Colo
r Black FW18, Color Black
S170, Color Black S150, Pri
ntex 35, Printex U (all manufactured by Degussa) and the like.

Examples of the pigment used for the yellow ink include C.I. I. Pigment Yellow
w1, C.I. I. Pigment Yellow 2,
C. I. Pigment Yellow 3, C.I. I.
Pigment Yellow 13, C.I. I. Pig
ment yellow 16, C.I. I. Pigmen
t Yellow 83 and the like. Examples of the pigment used for the magenta ink include C.I. I.
Pigment Red 5, C.I. I. Pigment
Red 7, C.I. I. Pigment Red 1
2, C.I. I. Pigment Red 48 (C
a), C.I. I. Pigment Red 48 (M
N), C.I. I. Pigment Red 57 (C
a), C.I. I. Pigment Red 112, C.I.
I. Pigment Red 122 and the like. Examples of the pigment used for the cyan ink include C.I. I. Pigment Blue 1, C.I. I.
Pigment Blue 2, C.I. I. Pigmen
t Blue 3, C.I. I. Pigment Blue
15: 3, C.I. I. Pigment Blue 16,
C. I. Pigment Blue 22, C.I. I. V
at Blue 4, C.I. I. Vat Blue 6 and the like can be mentioned, but it is not limited to these. In addition to the above, it is of course possible to use pigments newly produced for the present invention. The above-mentioned pigment is preferably 1% by mass with respect to the total amount of the stereoscopic image ink.
Not less than 20% by mass, more preferably not less than 2% by mass and not more than 12% by mass.
It may be used in a range of not more than mass%. Within this range, the physical properties of the obtained three-dimensional image ink will be more preferable.

Further, a dispersant may be used in combination to disperse the above-mentioned pigment. As the dispersant, any water-soluble resin can be used, but those having a weight-average molecular weight in the range of 1,000 to 30,000 are preferable, and those having a weight-average molecular weight of 3.0 or more are preferred.
Those having a range of 00 to 15,000 are preferably used. Specific examples of such water-soluble resins include hydrophobic monomers such as styrene, styrene derivatives, vinyl naphthalene, vinyl naphthalene derivatives, aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids, and acrylic monomers. Block copolymer, graft copolymer or random of at least two or more monomers selected from acid, acrylic acid derivative, maleic acid, maleic acid derivative, itaconic acid, itaconic acid derivative, fumaric acid, fumaric acid derivative Copolymers or salts thereof are exemplified.
These water-soluble resins are soluble in an aqueous solution in which a base is dissolved, and are alkali-soluble resins. Further, a homopolymer composed of a hydrophilic monomer or a salt thereof may be used.
It is also possible to use water-soluble resins such as polyvinyl alcohol, carboxymethylcellulose, and naphthalenesulfonic acid formaldehyde condensate. Incidentally, the water-soluble resin used as a dispersant for such a pigment,
It is preferable that the content is contained in the range of 0.1% by mass or more and 5% by mass or less based on the mass of the stereoscopic image ink.

If necessary, a surfactant may be added to the three-dimensional image ink. For example, fatty acid salts, higher alcohol sulfates, liquid fatty oil sulfates, anionic surfactants such as alkyl allyl sulfonates, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl Examples include nonionic surfactants such as esters, acetylene alcohol, and acetylene glycol, and one or more of these may be appropriately selected and used. On this occasion,
The amount of the surfactant added is preferably determined so that the surface tension of the three-dimensional image ink is 40 dyn / cm or less, and more preferably 30 dyn / cm or more and 35 dyn.
/ Cm or less. When the surface tension of the three-dimensional image ink is within this range, printing distortion (deviation of the landing point of the ink droplet) due to the wetting of the nozzle tip does not occur, which is more preferable.

Next, an example of a method of applying the three-dimensional image ink configured as described above to a recording medium will be described. FIG. 3 is a schematic cross-sectional view of the ink discharge head used in the present invention in the flow path direction, and FIG. 4 is a partially broken perspective view of the ink discharge head. The ink discharge head used in the present invention has a second ink flow path 4 on a substrate 1 provided with a heat generating portion 2 for applying thermal energy for generating air bubbles in ink, and a discharge port 11 on the second ink flow path 4.
The first ink flow path 3 is directly connected to the first ink flow path. A separation wall 5 made of a material having elasticity such as a metal, an inorganic material, or an organic material is disposed between the first and second ink flow paths. The foam ink in the second ink flow path is separated.

The separation wall of the portion located in the projection space upward in the surface direction of the heat generating portion 2 has a free-standing shape with the slit 8 at the discharge port 11 side and a fulcrum positioned at the common ink chambers 12 and 13 side. Since the movable member 6 is disposed so as to face the bubble generation region B, the movable member 6 operates to open to the first ink flow path side by foaming of the ink. . Here, the diameters of the ink flow paths 3 and 4 and the discharge ports 11 in the ink discharge head are 10 to
It is as thin as 30 μm.

Also in FIG. 4, a second ink flow path is provided on the substrate 1 on which the electrothermal transducer as the heat generating portion 2 and the wiring electrodes 18 for applying an electric signal to the electrothermal transducer are arranged. The separation wall 5 is arranged via a space that constitutes the above.

FIG. 5 is a view for explaining the positional relationship between the movable member 6 and the second ink flow path 4, and FIG. 5A is a view of the movable member 6 as viewed from above. FIG. 2B is a view as seen from above the second ink flow path 4 from which the separation wall 5 has been removed. FIG. 3C is a diagram schematically showing the arrangement relationship between the movable member 6 and the second ink flow path 4 by overlapping them. The second ink flow path 4 has a constricted portion 9 before and after the heat generating portion 2, and has a structure in which the pressure at the time of bubbling is prevented from traveling along the second ink flow path 4. As in the conventional case, when a head having the same flow path as the flow path for foaming and the flow path for discharging ink is provided, and a constricted portion is provided so that the pressure generated on the liquid chamber side from the heating section 2 does not escape to the common liquid chamber side. In this case, it is necessary to take a configuration in which the cross-sectional area of the flow path in the constricted portion does not become too small in consideration of the refill of the ink to be ejected.

However, in the structure disclosed here,
Most of the ejected ink is ink in the first ink flow path 3, and the ink in the second ink flow path 4 provided with the heat generating portion 2 is not consumed so much.
The ink filling amount of the ejection pressure generating section may be small. Therefore, the interval in the above-mentioned constricted portion 9 can be made very small as several μm to several tens μm, and the pressure generated during bubbling in the second ink flow path 4 does not escape much to the surroundings. Since this pressure is used as the discharge pressure via the movable member 6, higher discharge energy efficiency and higher discharge pressure can be achieved. However, the shape of the second ink flow path 4 is not limited to the above-described structure, and is not particularly limited as long as the pressure accompanying the bubble generation can be effectively transmitted to the movable member 6 side. The heat generating portion 2 has a shape of 40 × 105 μm, and the movable member 6 is disposed so as to cover the chamber in which the heat generating portion 2 is disposed. The size, shape, and arrangement of the heat generating portion 2 and the separation wall 5 are not limited to these, and may be any shape and arrangement in which the pressure during foaming can be effectively used as the discharge pressure.

FIG. 6 shows an example of the ink discharge head according to the present invention and the operation thereof. The heat generated by the driving of the heating unit 2 acts on the ink in the bubble generation area of the second ink flow path 4 so that the ink is described in JP-B-61-59914. This causes a film boiling phenomenon and bubbles. The pressure caused by the bubble generation is concentrated and propagates to the movable member 6 arranged in the discharge pressure generating portion, and the movable member 6 is moved along with the bubble growth as shown in FIG.
6B, it is displaced toward the first ink flow path 3 as shown in FIG. Due to the operation of the movable member 6, the first ink flow path 3 and the first ink flow path 4 are largely communicated with each other, and a pressure wave based on the generation of bubbles is mainly transmitted in the direction of the ejection port side of the first ink flow path 3. The ink is ejected from the ejection port by the propagation of the pressure wave and the mechanical displacement of the movable member.

FIG. 7 shows an example of a recording apparatus to which the ink discharge head 80 according to the present invention is attached. The ink ejection head 80 is mounted on a carriage HC that engages with a spiral groove 85 of a lead screw that rotates via driving force transmission gears 82 and 83 in conjunction with forward and reverse rotation of a driving motor 81. The carriage HC is reciprocated in the directions of arrows a and b together with the carriage HC by the power of the drive motor 81. The paper holding plate of the print paper P conveyed on the platen by a recording medium supply device (not shown)
The printing paper P is pressed against the platen over the moving direction of the carriage HC. A photocoupler is provided near one end of the lead screw. These are home position detecting means for confirming the presence of the lever of the carriage HC in this area and switching the rotation direction of the drive motor 81 and the like. In the drawing, reference numeral 84 denotes a support member that supports a cap member that covers the front surface of the above-described ink discharge head 80 having the discharge ports. An ink jet recording control unit for giving a signal to a heat generating unit provided in the ink ejection head 80 and controlling the driving of each mechanism described above is not shown here. The ink discharge head 80 writes on the printing paper P conveyed on the platen by a recording medium supply device (not shown) while reciprocating over the entire width of the printing paper P.

As an example of an ink jet recording system that can be used in the present invention, the generation of small ink droplets disclosed in US Pat. No. 3,060,429 is performed electrostatically, and the generated small droplets are used in accordance with a recording signal. Control the electric field to selectively attach these droplets on the recording medium, so-called T
The ele Type method can be used. Also, U.S. Pat. No. 3,596,275 and U.S. Pat.
No. 98030, etc., a droplet of ink with a controlled charge amount is generated by a continuous vibration generation method, and the droplet with the controlled charge amount is deflected by uniformly applying an electric field. A so-called Sweet method may be used, in which writing is performed on the recording medium by flying between the electrodes. Further disclosed in U.S. Pat. No. 3,416,153,
A so-called Hertz method in which an electric field is applied between the nozzle and the ring-shaped charging electrode to generate and atomize a small liquid of ink by a continuous vibration generation method to perform writing may be used. Further, an electric recording signal is applied to a piezoelectric vibrating element attached to an ink ejection head disclosed in US Pat. No. 3,747,120 to change the vibration into mechanical vibration of the piezoelectric vibrating element. The so-called Stemme method in which a small liquid of ink is ejected from the ejection port and written on the recording medium in accordance with the above method can be adopted.

Next, an example of the heating step in the present invention will be described with reference to FIG. In the figure, 23 is a heating unit, 2
2 and 24 are conveyance rollers, 25 is a sheet heater, 2
6 is a plate-shaped member. The heating unit 23 is disposed on the conveyance path of the recording medium 21 and is positioned with respect to the recording medium 21 so as to face an ink ejection head (not shown). The ink ejected from the ink ejection head flies toward the recording medium 21 and adheres. Then, the attached ink is heated by the heating unit 23, and the resin in the ink thermally expands to form a three-dimensional image. At this time,
The shorter the distance between the platen and the heating unit 23 is,
The penetration of the ink into the recording medium 21 is suppressed, and an image with a high swelling height can be formed. In addition, the heating unit 23
The recording medium 21 may be pre-heated not only at one place but also before the platen. Here, the heating unit 23 includes a metal such as aluminum, copper, iron, and stainless steel, or a ceramic such as SiC, BeO, and AlN, and includes a sheet-like heater 25 on a plate-like member 26 having good thermal conductivity. It is a bonded structure. The structure described here is an example of the configuration of the present invention, and the present invention is not limited to this.

[0045]

EXAMPLES In the following, "parts" and "%" are based on mass unless otherwise specified. First, as an example of a three-dimensional image ink, the creation of inks 1 and 2 will be described.

Example 1 Preparation of Ink 1 An expansion liquid was prepared by dissolving 10 parts of an alcohol-soluble nylon resin (Amilan CM4000 manufactured by Toray Industries, Inc.) in 100 parts of methanol. Next, after mixing and dissolving the components shown below, the mixture was filtered under pressure through a membrane filter having a pore size of 0.22 μm (trade name: Fluoropore Filter, manufactured by Sumitomo Electric Industries, Ltd.), and each of the yellow, cyan, magenta, and black inks I got In Ink 1, a water-soluble dye was used as a coloring material.

(Preparation of Yellow Ink Y1) I. Assid Yellow 11 2.5 parts Diethylene glycol 10 parts The above swelling liquid 10 parts Ion-exchanged water 77.5 parts In this case, the ratio of the alcohol-soluble nylon resin to the total amount of the ink is 0.91% by mass. In addition, the alcohol-soluble nylon resin was well dissolved in the ink finally obtained, and no precipitation or the like occurred.

(Composition of Magenta Ink M1) I. Acid Yellow 11 as C.I. I. The composition was the same as that of the yellow ink Y1 except that the red ink 133 was replaced.

(Composition of cyan ink C1) 2.5 parts of C.I. I. Acid Yellow 11 in 3.5 parts of C.I. I. The composition was the same as that of the yellow ink Y1 except that the ion-exchanged water was changed from 86.5 parts to 85.5 parts instead of the direct blue 78.

(Composition of Black Ink Bk1) 2.5 parts of C.I. I. Acid Yellow 11 in 3.5 parts of C.I. I.
86. Ion-exchanged water was used instead of Direct Black 17.
Yellow ink Y1 except for changing from 5 to 85.5 parts
The same composition was used.

Example 2 Preparation of Ink 2 In Ink 2, a pigment was used as a coloring material.

(Preparation of Yellow Ink Y2) Alkali-soluble resin (styrene-acrylic acid-ethyl acrylate; acid value 160, weight average molecular weight 8,000, solid content 2)
(0% aqueous solution) as a pigment dispersant, the following yellow dispersion was prepared. In addition, monoethanolamine was used as a neutralizing agent for the alkali-soluble resin.

Aqueous solution of alkali-soluble resin (solid content: 20%) 35 parts C.I. I. Pigment Yellow 83 25 parts Triethylene glycol 15 parts Isopropyl alcohol 5.5 parts Ion-exchanged water 135 parts The above components were charged into a batch-type vertical sand mill (made by Imex), filled with 1 mm diameter glass beads as a medium, and cooled with water. Dispersion processing was performed for 3 hours. The dispersion was centrifuged to remove coarse particles to obtain a yellow dispersion having an average particle diameter of 10 mm.

Next, N-methoxymethylated nylon 12 resin (trade name: Toresin G550, Teikoku Chemical Industry Co., Ltd.)
20 parts of methanol and n-butanol 4
The swelling liquid was prepared by dissolving in 0 parts of a mixed alcohol. After adding 20 parts of the swelling liquid and 100 parts of ion-exchanged water to the above yellow dispersion, the mixture is sufficiently stirred and the pH is adjusted.
9.5 yellow ink Y2 was obtained. In this case, the ratio of the alcohol-soluble nylon resin to the total amount of the ink is 0.99% by mass. In addition, the alcohol-soluble nylon resin was well dissolved in the ink finally obtained, and no precipitation or the like occurred.

(Preparation of Magenta Ink M2) The following components were mixed using the alkali-soluble resin aqueous solution used for preparing the yellow ink Y2, and then the yellow ink Y2 was prepared.
The dispersion processing was performed under the same conditions as in the case of preparation of No. 2.

A. aqueous solution of alkali-soluble resin (solid content: 20%) 20 parts I. Pigment Red 122 24 parts Glycerin 15 parts Isopropyl alcohol 4 parts Deionized water 133 parts The average particle diameter of the obtained magenta dispersion was 110 millimicrons.

Next, N-methoxymethylated nylon 12 resin (trade name: Toresin G550, Teikoku Chemical Industry Co., Ltd.)
20 parts of methanol and n-butanol 4
The swelling liquid was prepared by dissolving in 0 parts of a mixed alcohol. After adding 20 parts of the swelling liquid and 100 parts of ion-exchanged water to the above yellow dispersion, the mixture is sufficiently stirred and the pH is adjusted.
9.4 magenta ink M2 was obtained. In this case, the ratio of the alcohol-soluble nylon resin to the total amount of the ink is 1.1% by mass. In addition, the alcohol-soluble nylon resin was well dissolved in the ink finally obtained, and no precipitation or the like occurred.

(Preparation of Cyan Ink C2) The following components were mixed using the aqueous alkali-soluble resin solution used in preparing the yellow ink Y2, and then subjected to dispersion treatment under the same conditions as in the preparation of the yellow ink Y2. Was.

Aqueous solution of alkali-soluble resin 30 parts C.I. I. Pigment Blue 15:24 parts Diethylene glycol 20 parts Isopropyl alcohol 4 parts Deionized water 135 parts The average particle diameter of the obtained cyan dispersion was 120 millimicrons.

Next, N-methoxymethylated nylon 12 resin (trade name: Toresin G550, Teikoku Chemical Industry Co., Ltd.)
20 parts of methanol and n-butanol 4
The swelling liquid was prepared by dissolving in 0 parts of a mixed alcohol. After adding 20 parts of the swelling liquid and 100 parts of ion-exchanged water to the above yellow dispersion, the mixture is sufficiently stirred and the pH is adjusted.
9.2 cyan ink C2 was obtained. In this case, the ratio of the alcohol-soluble nylon resin to the total amount of the ink is 1.0% by mass. In addition, the alcohol-soluble nylon resin was well dissolved in the ink finally obtained, and no precipitation or the like occurred.

(Composition of Black Ink Bk2) The following components were mixed and heated to 70 ° C. in a water bath to completely dissolve the resin component.

Styrene-acrylic acid-acrylate copolymer (acid value 160, weight average molecular weight 8,000) 1.5 parts Monoethanolamine 1.2 parts Ion exchange water 81.5 parts Carbon black MCF88 was added to this solution. (Mitsubishi Chemical)
10 parts and 1 part of isopropyl alcohol were added, and after premixing for 30 minutes, dispersion treatment was performed under the following conditions.

Dispersing machine: Sand grinder (made by Igarashi Kikai) Grinding media: Zirconium beads Filling ratio of grinding media: 50% (volume) Grinding time: 3 hours Further centrifugation (12,000 rpm, 20 minutes)
Was performed to remove coarse particles to obtain a dispersion.

Next, the following components were mixed to obtain a black ink Bk2 having a pH of 9.5.

The dispersion 30 parts Glycerin 15 parts Ethylene glycol 5 parts Isopropyl alcohol 4 parts Ion-exchanged water 25 parts The expansion liquid 20 parts In this case, the ratio of the alcohol-soluble nylon resin to the total amount of the ink is 3.4% by mass. It is. In addition, the alcohol-soluble nylon resin was well dissolved in the ink finally obtained, and no precipitation or the like occurred.

(Example 3) Using the inks 1 and 2 obtained as described above, a stereoscopic image was formed using Canon PPC paper as a general-purpose recording medium. The same recording apparatus and heating means as those shown in FIGS. 7 and 8 were used.
And the above inks 1 and 2 were supplied from an ink tank (not shown). The ejection amount per dot from the ink ejection head is 80 pl / d
After the heating step, the height of the one dot raised from the recording medium by this one dot was about 0.8 mm, and there was no variation due to the position of the recording medium. The quality of the three-dimensional image obtained in this example was good, no clogging of the ink occurred, the expansion rate in each heating step was constant, and the yield was good.

[0067]

The three-dimensional image ink of the present invention contains a coloring material and a resin which is soluble in alcohol and thermally expands.
By a three-dimensional image forming method including a writing step and a heating step by an inkjet recording method, a uniform and high-quality three-dimensional image can be obtained on a general-purpose recording medium with a high yield.

[Brief description of the drawings]

FIG. 1 is a schematic view of a three-dimensional image formation in the present invention.

FIG. 2 is a schematic view of forming a three-dimensional image in the present invention.

FIG. 3 is a schematic cross-sectional view of an ink ejection head.

FIG. 4 is a partially cutaway perspective view of an ink ejection head.

FIG. 5 is a schematic diagram of an ink flow path.

FIG. 6 is a schematic diagram illustrating the operation of the ink ejection head.

FIG. 7 is a schematic perspective view of a recording apparatus.

FIG. 8 is a diagram showing a position of a heating unit.

FIG. 9 shows a conventional example of a writing process for forming a dot image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Heating part 3 Ink flow path 4 Ink flow path 5 Separation wall 6 Movable member 8 Slit 9 Narrowed part 11 Discharge port 12 Common ink chamber 13 Common ink chamber 18 Wiring electrode 21 Recording medium 22 Transport roller 23 Heating section 24 Transport Roller 25 Sheet heater 26 Plate member 80 Ink ejection head 81 Drive motor 82 Driving force transmission gear 83 Driving force transmission gear 84 Support member 85 Spiral groove B Bubble generation area HC Carriage P Print paper

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B41J 3/04 101Y

Claims (10)

[Claims] 1. A writing step of forming a dot image made of ink in an image forming area of a recording medium using an ink jet recording method, and simultaneously fixing and drying the ink on the recording medium and simultaneously performing thermal expansion. A heating step of causing the ink to contain a coloring material and an alcohol-soluble resin that thermally expands during the heating step. 2. A bubble jet, wherein the ink jet recording system rapidly raises the temperature of the ink to cause film boiling, thereby generating bubbles in the ink, and discharging the ink using pressure generated when the bubbles are generated. 2. The method according to claim 1, wherein the recording method is a recording method. 3. The bubble jet recording system according to claim 1, wherein the bubble jet recording method includes an ejection port for ejecting the ink, a bubble generation region for generating the bubble in the ink, and an ink flow path communicating with the ejection port. 3. The three-dimensional image forming method according to claim 2, wherein an ink discharge head that discharges ink by pressure generated when bubbles are generated is used. 4. The three-dimensional image forming method according to claim 1, wherein the heating step is performed by a heating unit disposed on a conveyance path of the recording medium. 5. The three-dimensional object according to claim 1, wherein the heating step is performed by a heating unit disposed on the recording medium at a position facing the ink discharge head. Image forming method. 6. The method according to claim 1, wherein the resin is an alcohol-soluble nylon resin. 7. The method according to claim 1, wherein the color material is a dye, a pigment, or a mixture of a dye and a pigment. 8. A three-dimensional image ink, comprising: a color material; and an alcohol-soluble resin that thermally expands during a heating step of fixing and drying a dot image made of the ink on a recording medium. 9. The three-dimensional image ink according to claim 8, wherein the resin is an alcohol-soluble nylon resin. 10. The three-dimensional image ink according to claim 8, wherein the coloring material is a dye, a pigment, or a mixture of a dye and a pigment.