JPH0220384A - Image recording - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Skin Enrichment 1 The present invention relates to an image recording method for forming an image using light energy and thermal energy.

Various methods of forming images by photopolymerization or thermal transfer are known. Methods for forming plates and images by photopolymerization include, for example, Japanese Patent Publication No. 37-18979 and Japanese Patent Publication No. 38-1989.
As described in Japanese Patent No. 9672, a layer of a photopolymerizable composition is provided on a support, and imagewise exposure is performed to form an image consisting of a polymerized/unpolymerized pattern. There is a method of transferring to another support by utilizing differences in adhesiveness or transferability.

In addition, as described in Japanese Patent Publication No. 39-8436, after exposing a photopolymerizable composition layer sandwiched between a support and a covering sheet, the support and the covering sheet are separated to form an image. There is a way to get it.

Further, US Pat. No. 4,399,209 describes an image forming method in which photopolymerization is applied to color formation. This method reacts with the color forming layer to produce yellow,
A recording medium exhibiting the three primary colors magenta and cyan and in which photocurable microcapsules having wavelength selectivity are randomly provided is sequentially exposed to light in the form of a positive image corresponding to the three primary colors, and after the exposure is completed, the recording medium is The medium is pressurized to destroy the uncured microcapsules and cause them to react with the coloring layer to develop color, thereby obtaining a multicolor image.

Also, US Pat. No. 4,416,966 discloses a self-contained imaging system in which the color developer is on the same support surface as the photosensitive microcapsules. In this system, after being exposed to light converted according to the recorded image, mainly ultraviolet light, the image-forming sheet is passed between pressure rolls to destroy the microcapsules and release the internal phase of the microcapsules in an imagewise manner. let The color former is then soluble in a developer, usually provided in a separate layer, where it reacts to form a multicolor image.

On the other hand, the thermal transfer recording method was developed in recent years in line with the rapid development of the information industry, and this method involves applying heat-melting ink, which is made by dispersing a colorant in a heat-melting binder, onto a ribbon-shaped support. Recording is performed on recording paper using an ink ribbon made of That is, the ink ribbon is placed on the recording paper so that its thermally transferable ink layer is in contact with the recording paper, and both are conveyed between a thermal head and a platen, and an image signal is transferred from the support side of the ink ribbon by the thermal head. In addition to applying pulsed heat according to the
By pressing the two together and transferring the melted ink onto the recording paper, an ink image corresponding to the shape of heat application is recorded on the recording paper.

Apparatuses using the above recording method have been widely used in recent years because they are small and lightweight, do not make noise, and can record on plain paper.

In the conventional methods described above, in the case of image forming methods using photopolymerization, the means used for image formation mainly forms images by irradiating only ultraviolet light, that is, light energy, onto the recording medium. Therefore, in order to form clear images at high speed, it has been necessary to use a photosensitive material that is highly sensitive to light or to irradiate it with high energy light.

However, in the case of a highly sensitive recording medium that utilizes only a photoreaction, the sensitivity when irradiated with light is high and the storage stability near room temperature is poor. In addition, since the device that obtains high-energy light is large, when it is incorporated into an image forming device,
As the size of the device increases, the cost of the device also increases, which is undesirable from a practical standpoint. Furthermore, in order to obtain high-resolution recording quality using an image forming method using photopolymerization, a positive film for exposure must be prepared. Moreover, since the positive film is produced by a method such as silver halide photography, there are problems in that the work process is complicated and the equipment becomes large, which requires time and cost.

Furthermore, the method of forming images using only light energy is useful when outputting images in response to external signals, such as in printers, or when reading images from color originals, such as in color copying machines, using color image scanners. It is not suitable for applying image information to a recording medium after converting it into a digital signal. That is, when irradiating high-energy light, it is necessary to use short wavelength, mainly ultraviolet light, but a digitally controllable light source for ultraviolet light is currently not available.

For example, optical heads such as liquid crystal shutter arrays and LED arrays have been devised as methods for obtaining digital light sources, but even though these are suitable for miniaturization, liquid crystal molecules deteriorate at wavelengths in the ultraviolet region. Ultraviolet light is difficult to extract stably.

In particular, the recording media used in the image forming methods described in the above-mentioned U.S. Pat. No. 4,399°209 and U.S. Pat. Because of this, the stability of recorded images is poor due to the quality of the wood.

Furthermore, in image forming methods in which microcapsules are destroyed to develop color, the contents of the microcapsules are often a photosensitive composition that is in a liquid phase at room temperature in order to facilitate development by applying pressure after exposure. For this reason, a recording medium in which the microcapsules are provided on a support has poor storage stability, and the resulting image also has a monomer odor due to the destruction of unreacted microcapsules, which is undesirable from a practical standpoint.

On the other hand, in the thermal transfer recording method, especially when trying to obtain a multicolor image, it is necessary to repeat transfer to overlap the colors.

To do this, it is necessary to install multiple thermal heads, or to make the recording paper make complicated movements such as stopping and reversing, which not only makes color misalignment unavoidable, but also makes the entire device large and complicated. There is a problem.

In order to solve the above-mentioned problems, the present applicant uses a recording medium that undergoes a rapid reaction and irreversibly changes transfer characteristics when thermal energy and light energy are applied, and uses a recording medium that changes the transfer characteristics according to the image signal. An image forming method in which an image is formed on a recording medium due to the difference in color and this image is transferred to a recording medium was disclosed in Japanese Patent Laid-Open No. 1983-
It was proposed in No. 17t195. According to this method, a multicolor, high-quality image can be obtained without making complicated movements of the recording medium. Furthermore, when transferring the image on the recording medium formed by this method to the recording medium, the applicant has further disclosed that after the image on the recording medium is transferred to the intermediate transfer medium, the image on the intermediate transfer medium is transferred to the recording medium. We also proposed an image recording method that makes it possible to perform stable recording even on objects with large variations in surface characteristics by transferring images to
Japanese Patent Application No. 63-3780) shows that even higher image quality is desired in such a recording method.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image recording method capable of performing stable, high-quality recording even on transfer objects with large variations in surface characteristics.

11101 As a result of intensive research, the inventors of the present invention formed an image by selectively transferring the image forming element on the binder layer onto an intermediate transfer medium, and further transferred the image to a recording medium made of plain paper or the like. In the image forming method for transferring onto a body, actively transferring a part of the binder layer onto the image transferred onto the intermediate transfer medium,
It has been found that the transfer rate of the image forming element when an image formed on the intermediate transfer medium is transferred to a recording medium and further the image quality of the transferred recorded image on the recording medium can be significantly improved.

The image forming method of the present invention is based on the above knowledge, and more specifically, it includes a binder layer on a base material and a distribution of an image forming element whose transfer characteristics change by applying light energy and thermal energy. A transfer image is created by applying light energy and thermal energy to the distributed layer under conditions that at least one type of energy of light energy and thermal energy is applied in correspondence with the recorded information. an intermediate transfer step in which a recording medium on which the transferred image is formed is brought into contact with an intermediate transfer medium and then separated to transfer the transferred image to the intermediate transfer medium; and a transfer image is transferred to the intermediate transfer medium. Post the image #! forming a transferred recorded image by transferring it to a medium, and when separating the recording medium and the intermediate transfer medium in the intermediate transfer step,
It is characterized in that the temperature of the recording medium is maintained above the softening point of the binder.

The transfer characteristic here refers to the property of the image forming element to transfer to a recording medium, and a decrease in the transfer characteristic means that it becomes difficult to transfer to the same recording medium.

Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary.

A preferred embodiment of the present invention will be described with reference to the schematic cross-sectional view in the thickness direction of a transfer recording medium shown in FIG.

The recording medium 1 used in the present invention consists of a binder layer 1b provided on a base material 1c and a distribution layer 1a of image forming elements. In the following description, a mode in which the recording medium 1 for color recording is used, that is, each image forming element 2 constituting the distribution layer 1a is one of yellow (Y), magenta (M), and cyan (C). A case in which different types of coloring components are contained will be explained. However, the coloring components contained in each image forming element are not limited to yellow (Y), magenta (M), and cyan (C), and any coloring material may be used depending on the purpose. Moreover, the number of types of coloring components contained in one type of image forming element may be one or more types. Image forming element 2
It is sufficient that the distribution is uniform to the extent that the reproducibility of the recorded image is substantially ensured, and the distribution does not necessarily need to be microscopically regularly arranged.

The image forming element 2 has wavelength selectivity due to the coloring components it contains. That is, for example, when the image forming element 2 (Y) containing a yellow coloring component is exposed to heat and light having a wavelength of λ, crosslinking rapidly progresses and the image forming element 2 (Y) is cured. and the wavelength λ
When light other than 1 is added, crosslinking does not proceed. Similarly, an image forming element 2 containing, for example, a magenta coloring component
(M) is heat and light of wavelength λ2, for example, image forming element 2 (C) containing a cyan coloring component is rapidly crosslinked and cured when heat and light of wavelength λ are respectively applied. .

FIGS. 2(a) to (e) show that an image is formed by applying thermal energy modulated according to a recording signal to the recording medium 1 along with light energy of a wavelength selected depending on the color tone of the image forming element to be cured. FIG. 3 is a schematic cross-sectional view in the thickness direction of a recording medium showing a forming process. Here, "modulation" refers to changing the position where energy is applied according to the image signal, and "both" refers to the case where light energy and thermal energy are applied at the same time, and the case where light energy and thermal energy are applied separately. It includes both cases where it is given to

Next, an image recording method of the present invention using the recording medium 1 having the above-described configuration will be described.

Referring to the schematic cross-sectional view in the thickness direction of the recording medium in FIG. 2(a), first, the recording medium 1 is stacked on the thermal head 20,
Light is irradiated to cover the heat generating area of the thermal head 20. In this light irradiation, wavelengths to which the image forming element body 2 reacts are sequentially irradiated. For example, if the image forming element 2 is yellow (Y), magenta (M), or cyan (C),
), the wavelength λ1λ2,
Light of λ3 is sequentially irradiated. That is, first, light of wavelength λ1 is irradiated from the distribution layer 1a side of the image forming element 2 of the recording medium 1, and at the same time, for example, the heating resistor of the thermal head 20 is
0b, 20d, and 20a generate heat. Then, the image forming element 2 (Y) exhibiting yellow color is exposed to both heat and light of wavelength λ1 (the hatched part in FIG. 2(a); hereafter, the hardened image forming element 2 (Y) The image forming element 2 (indicated by hatching) is cured. Next, see Figure 2 (
As shown in b), when the image forming element 1a is irradiated with light of wavelength λ2 and the heating resistors 20a, 20e, and 20f are made to generate heat, the image forming element 2 exhibits a magenta color (
In M), the image forming element to which both heat and light of wavelength λ is applied is cured. Further, as shown in FIG. 2(c), when the image forming element body 2 is irradiated with light of wavelength λ and the heating resistors 20a, 20b, and 20e are caused to generate heat,
Heat and wavelength λ3 of the image forming element 2 (C) exhibiting cyan color. The image forming element to which both light and light are applied is cured.

Image forming element 2 that was not finally cured in this way
As a result, a transferred image is formed in the distribution layer 1a of the element body.

Here, we have shown a method of forming an image by irradiating the entire area of the thermal head with light and selectively generating heat from the heating resistor of the thermal head. In the case of the thermal head shown in FIG. 2, in which all the heating resistors generate heat, a multicolor image can be similarly formed by selectively irradiating light.

Next, as shown in FIG. 3(a), the recording medium 1 on which the transferred image has been formed and the intermediate transfer medium 3 are brought into contact with each other so that the distribution layer 1a of the image forming element is in contact with the intermediate transfer medium 3. Then, heat and pressure is applied from the recording medium 1 or intermediate transfer medium 3 side to transfer the transferred image onto the intermediate transfer medium 3.
Form an image on top.

In the image forming method of the present invention in which the transfer image formed on the recording medium 1 is first transferred to the intermediate transfer medium 3,
Since it is easy to appropriately select transfer conditions such as temperature and pressure in accordance with the surface characteristics of the intermediate transfer medium 3, it is possible to easily select transfer conditions such as temperature and pressure in accordance with the surface characteristics of the intermediate transfer medium 3, regardless of the surface characteristics of the recording medium (final transfer medium) made of plain paper, etc. , the transfer conditions in this intermediate transfer step can be optimized.

As the intermediate transfer medium, it is preferable to use, for example, an intermediate transfer medium made of a material described below and having uniform surface characteristics. In this case, the conditions (
In other words, the recording medium 1 is
The upper transfer image can be transferred, and therefore unnecessary (ie, non-selective) transfer can be suppressed from occurring in the non-transfer area. In addition, since the image forming element 2 can be transferred under milder conditions, it is possible to prevent the image forming element 2, which should not originally be transferred, from being transferred together with the image forming element 2 surrounding the image forming element 2. Therefore, the image transferred onto the intermediate transfer medium 3 can be of higher quality than when directly transferred onto general paper or the like.

In the present invention, in this intermediate transfer step, the temperature of the recording medium 1 when the recording medium 1 and the intermediate transfer medium 3 are separated is maintained above the softening point of the binder 1b. As a result, a desired image is formed on the intermediate transfer medium 3 based on the selective transfer of the image forming element 2 from the recording medium 1. At this time, a binder layer is formed on the image forming element 2. A portion of the binder (not shown) constituting 1b is transferred onto the intermediate transfer medium 3 while remaining attached.

Next, as shown in FIG. 3(b), the intermediate transfer medium 3 on which the image has been formed and the recording medium 4 made of plain paper or the like are transferred so that the image on the intermediate transfer medium 3 is transferred to the recording medium 4. heating from the intermediate transfer medium 3 or recording medium 4 side with the surfaces touching,
The image on the intermediate transfer medium is transferred onto the recording medium 4 by applying pressure. At this time, unnecessary image forming elements 2 are not attached to the intermediate transfer medium 3, so even if the conditions for this transfer are strengthened (that is, even if the transfer temperature and transfer pressure are increased), no unnecessary image forming elements 2 are attached to the intermediate transfer medium 3. The necessary image forming element 2 is not transferred to the recording medium 4. Therefore, in order to make the transfer rate of the image on the intermediate transfer medium 3 sufficiently high even for the recording medium 4 with large variations in surface characteristics, even if the transfer conditions are strengthened, the image such as fogging may occur. No deterioration of quality will occur.

In the present invention, the binder on the intermediate transfer image on the intermediate transfer medium 3 (on the recording medium 4 side) functions as an adhesive for bonding the intermediate transfer image to the recording medium 4. The transfer rate of the intermediate transfer image to the recording medium 4 is improved, and the image quality of the transferred recorded image formed on the recording medium 4 due to this transfer is also improved.

Intermediate transfer media with uniform surface characteristics preferably used in the present invention include metals such as aluminum and stainless steel;
Examples include intermediate transfer media made of polymers such as polyethylene terephthalate and polyimide, or synthetic paper. The shape of the intermediate transfer medium may be a sheet, an endless film, a roll, or the like.

In the recording medium 1 used in the present invention, the image forming element 2 whose transfer characteristics change upon application of light energy and thermal energy contains at least a sensitive component and, if necessary, a binder. (binder), thermal polymerization inhibitor, plasticizer, colorant, surface smoothing agent, and other additives.

The sensitive component preferably includes a photopolymerization initiator and a polymerization component. The polymerization component preferably consists of a monomer, oligomer, or polymer having unsaturated double bonds.

As the photopolymerization initiator used in the present invention, carbonyl compounds, halogen compounds, azo compounds, organic sulfur compounds, etc. are preferably used, and more specifically, for example, acetophenone, benzophenone, coumarin, xanthone, thioxanthone, chalcone, and styryl. Aromatic ketones and their derivatives such as styryl ketone; diketones and their derivatives such as benzyl, acenaphthenequinone, and camphorquinone; anthraquinone sulfonyl chloride,
Quinoline sulfonyl chloride, 2.4゜6-tris (
Examples include halogen compounds such as (trichloromethyl)-S-triazine; however, the present invention is not limited thereto.

Further, when the present invention is applied to multicolor image formation, as described above, the image forming element 2 constituting the transfer recording layer 1a needs to have wavelength dependence depending on the type of colorant.

In other words, when the transfer recording layer 1b is composed of image forming elements 2 of n types of colors, the application of thermal energy and light of different wavelengths for each colored color, that is, the application of n types of different wavelengths, suddenly causes The distribution layer of the image forming element is composed of a combination of sensitive components whose reaction rates change. As such a combination of photopolymerization initiators, for example, the following combinations can be used.

For example, a photopolymerization initiator using a combination of S-triazine having a triheromethyl group has a maximum sensitivity of about 430 to 5.
It is around 00 nm.

A photopolymerization initiator using a combination of tertiary amines and the like has a maximum sensitivity around 370 to 400 nm.

Furthermore, a photopolymerization initiator using a combination of tertiary amines and the like has a maximum sensitivity around 300 to 350 nm.

As described above, by changing the maximum sensitivity wavelength range of the photopolymerization initiator used, it is possible to impart wavelength selectivity to the image forming element. Therefore, if the above photopolymerization initiator is used, it becomes possible to separate the three colors, and furthermore, it becomes possible to develop full-color recording. In addition, in the present invention, by using together with the photopolymerization initiator a compound that has large absorption in the ultraviolet to visible range, such as an ultraviolet absorber, the photopolymerization initiator's sensitive wavelength range is narrowed, and the photopolymerization initiator's spectral It is also possible to increase the quality.

Examples of polymers, oligomers, and polymers having unsaturated double bonds include polyisocyanates (which may be reacted with polyols as necessary), alcohols, and amines containing unsaturated double bonds. Urethane acrylates or urethane methacrylates synthesized by polyaddition reaction with epoxy resin; epoxy acrylates synthesized by addition reaction between epoxy resin and acrylic acid or methacrylic acid; or polyester acrylates,
Examples include spinacrylades and polyether acrylates, but the present invention is not limited thereto.

In addition to the above, the polymer has a main skeleton such as gd polyalkylene, polyether, polyester, polyurethane, etc., and has an acrylic group, methacrylic group, cinnamoyl group, cinnamylidene acetyl group, furyl acryloyl group, or silicate group in the side chain. Examples include those into which polymerizable or crosslinkable reactive groups such as acidic esters are introduced, but the present invention is not limited thereto.

In addition, it is desirable that the monomers, oligomers, and polymers mentioned above are semi-solid or solid at room temperature, but even if they are liquid monomers, they can be made into a semi-solid or solid by mixing with the binder described below. It can be used as long as it is maintained. The ratio of the photopolymerization initiator to the polymerization component as described above is preferably 1:5 to 1:1000 (more preferably 1:10 to 1:100).

The aforementioned monomer, oligomer or polymer having an unsaturated double bond and the photopolymerization initiator may be used in combination with a binder. As such a binder, any organic polymer having compatibility with the polymer, oligomer or polymer having unsaturated double bonds can be used without particular limitation. Examples of such organic polymers include polyacrylic acid alkyl esters such as polymethyl acrylate and polyethyl acrylate; polymethacrylic acid alkyl esters such as polymethyl methacrylate and polyethyl methacrylate; or methacrylic acid copolymers; Copolymers such as acrylic acid copolymers and maleic acid copolymers; or chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene; polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, and copolymers thereof; Examples include polyvinyl alkyl ether, polyethylene, polypropylene, polystyrene, polyamide, polyurethane, chlorinated rubber, cellulose derivatives, polyvinyl alcohol, and polyvinylpyrrolidone, but the present invention is not limited thereto. These binders may be used alone or in combination of two or more at an appropriate mixing ratio. Further, waxes may be used as binders, regardless of whether they are compatible or incompatible. The ratio of the sensitive component to the binder as described above is 1.
:0.05~1:3 (even 1:0.05~1:0.8
) is preferable.

The colorant is a component contained in order to form an optically recognizable image, and various pigments and dyes are used as appropriate. Examples of such pigments and dyes include inorganic pigments such as carbon black, yellow lead, molybdenum red, and red red; Hansa Yellow, Benzidine Yellow, Brilliant Carmine 6B, Lake Red C, and Permanent Red F5.
R, Phthalocyanine Blue, Victoria Blue Lake,
Examples include organic pigments such as fast sky blue; coloring agents such as leuco dyes and phthalocyanine dyes.

The amount of the colorant is preferably 0.1 to 30 parts by weight based on 100 parts by weight of the total amount of the binder, photoinitiator, and monomer, oligomer, or polymer having unsaturated double bonds.

Furthermore, additives such as a thermal polymerization inhibitor and a plasticizer may be added to the image forming element 2 as necessary.

The recording medium 1 used in the present invention is obtained by mixing and melting the components constituting the image forming element 2, and obtaining the mixed and melted mixture as a minute image forming element by a spray drying method, an emulsion granulation method, etc. This can be obtained by applying this onto the binder layer 1b provided on the base material 1c. Further, from the viewpoint of preventing a decrease in sensitivity during storage of a recording medium and further improving image resolution, it is preferable to microcapsule the image forming element.

When using microcapsules as the image forming element 2, the core portion contains the above-described material. In this case, the materials used for the wall material of the microcapsules include gelatin and cellulose materials such as gum arabic, ethyl cellulose, and nitrocellulose; and urea-formalin, nylon, polyester, polyurethane, polycarbonate, maleic anhydride copolymers, Examples include polymeric materials such as vinylidene chloride, polyvinyl chloride, polyethylene, polystyrene, and polyethylene terephthalate (PUT).

Further, the particle size of the image forming element body 2 constituting the distributed layer 1a is 1
~20μ is preferred, particularly 3~10μ. Further, when the image forming element is composed of microcapsules, the average particle diameter of the microcapsules is preferably 1 to 20 μm, particularly preferably 3 to 10 μm. Further, the particle size distribution of the microcapsules is preferably ±50% or less, particularly preferably ±20% or less with respect to the number average diameter. The thickness of the wall material of the microcapsule is preferably 0.1 to 2.0 μm, particularly preferably 0.1 to 0.15 μm.

Any conventionally known method can be applied as the microencapsulation method, such as simple coacervation method,
Complex coacervation method, interfacial polymerization method, 1
The n-situ polymerization method, interfacial precipitation method, phase separation method, spray drying method, air suspension coating method, mechanochemical method, etc. are used.

As the binder, thermoplastic materials such as polyester, ethylene-vinyl acetate copolymer, polyamide, polyolefin, polyurethane, polychloroprene, nitrile rubber, and styrene-butadiene are preferably used. This binder is manufactured using the ring and ball method (R&B method, JIS
The softening point determined by K2207) is preferably 60 to 150°C, more preferably 80 to 140°C.

As the base material, a relatively heat-resistant plastic film such as polyester, polycarbonate, triacetylcellulose, nylon, or polyimide, or paper such as condenser paper or glassine paper is used. In the case of a film-like base material, the thickness is about 1 to 30 μm, more preferably 3 to 30 μm.
The thickness is preferably about 15 μm.

On these base materials 1c, the binder can be dissolved in a solvent or emulsified, applied with an applicator, and then the solvent or water can be volatilized, or the material can be melted by heating on a hot plate. The binder layer 1b is formed on the base material 1c using a method of coating with a wire bar and returning to room temperature, or a method of spraying or gravure printing. When the image forming element 2 is bound, the image forming element 2 may be attached after the binder layer 1b is made adhesive by heating again.

Methods for adhering the image forming element in a single layer onto a binder having adhesive properties include not only the simple sprinkling method, but also the method of overlaying the image forming element on a separately prepared support. A method may also be used in which a base material coated with a binder is conveyed in contact with a container containing an image forming element in advance. Then, if necessary, a means for removing the excess amount using, for example, an air gun may be provided.

The present invention will be described in more detail below with reference to Examples.

[Example Table 1 Table 2 Table 3 Compositions consisting of the components shown in Tables 1, 2, and 3 above were separately microencapsulated according to the following method.

That is, first, 10 g of a composition consisting of the ingredients shown in Table 1.
was mixed with 20 g of methylene chloride, and the nonionic surfactant Noniball 100 (manufactured by Sanyo Chemical Industries, Ltd.) was mixed with 20 g of methylene chloride.
A few drops of HLB value 13) and 1 g of gelatin were mixed in 200 ml of water, and mixed with a homomixer under heating at 60° C. to 8,000 to 10. The mixture was emulsified by stirring at OOO rpm to obtain oil droplets with an average particle size of 26 μm.

Stirring was further continued at 60° C. for 30 minutes, and methylene chloride was distilled off to make the average particle size of the oil droplets 10 μm. To this was added 20+ ol of water in which 1 g of gum arabic was dissolved, and while slowly cooling to 5°C, NH4OH (ammonia) water was added to make the pH 11 or higher to obtain a microcapsule slurry, and glutaraldehyde was added to this at 5°C. 1.0 ml of a 20% aqueous solution was slowly added and the temperature was returned to room temperature to harden the capsule wall.

Next, solid-liquid separation was performed using a Nutsche filter, and the
C. for 10 hours to obtain a microcapsule-shaped image forming element 2.

Next, using 10 g of a composition consisting of each component in Table 2 and 10 g of a composition consisting of each component in Table 3,
Microencapsulation was carried out in the same manner as above, and a total of three types of image forming elements 2 were obtained.

The particle size of the obtained image forming element was in the range of approximately 8 to 12 μm. In the light absorption characteristics shown in the graph of FIG. 4, the photopolymerization initiator in the image forming element consisting of the components shown in Table 1 absorbs light in the band of graph A to initiate a reaction. The photopolymerization initiator in the image forming element consisting of the components shown in Table 2 absorbs light in the band of graph B to initiate a reaction, and the photopolymerization initiator in the image forming element consisting of the components shown in Table 3 The photopolymerization initiator absorbs light in the band of graph C to initiate the reaction.

The colors of each image forming element were magenta (Table 1), cyan (Table 2) and yellow (Table 3). Above 3
Recording medium 1 used in the present invention was prepared by the method described below using a mixture of equal amounts of different types of image forming elements.

First, a PET film with a thickness of 6 μm was used as a base IC, and a toluene solution of polyester adhesive Polyvarnish fi-Lp-olt (softening point 112°C) manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd. was applied onto this PET film after drying. Thickness is approximately 1μm
It was applied so that After this application, the PET film side (the side to which no adhesive is applied) of the dried PET film is brought into close contact with a hot plate heated to about 100°C, and the adhesive layer obtained above is placed on the adhesive layer formed above. After sprinkling an excess amount of an equal mixture of three types of image forming elements, PET
The film was peeled off the hot plate. Next, after removing the image forming element not in contact with the adhesive layer with an air gun, the PET film with the image forming element provided thereon was placed between two wooden rollers (rotation speed: 3
rpm) to bring the image forming element into close contact with the PET film. The surface temperature of the roller on the PET side was maintained at 120°C.

The recording medium 1 thus obtained was wound and placed in an apparatus whose schematic cross-sectional view in the thickness direction of the recording medium is shown in FIG.
0).

In this example, a lamp 21 (20W health line fluorescent lamp F manufactured by Toshiba Corporation) having a peak wavelength of 335 nm is used as a light source.
L20SE) and a lamp 2 with a peak wavelength of 390 nm.
2 (Toshiba Corporation 20W fluorescent lamp FLI 0A70E39
) and a lamp 23 (20W fluorescent lamp FL10A70B manufactured by Toshiba Corporation) having a peak wavelength of 450 nm were used.

The energizing pulse when the thermal head 20 generates heat is 0.5W/
d o t, 2 at duty ratio (Duty) 33.3%
The application time was 0 m5ec.

Referring to FIG. 5, the transfer recording medium 1 was unwound from the supply roll 11 and taken up by the take-up roll 112 of the recording medium 1. Further, the OHP PET sheet 24, which is an intermediate transfer medium, is transferred from the cassette 30 to the transfer roll 25 and the pressure roll 2.
It was supplied to a transfer section consisting of 6. The drive of the apparatus shown in FIG. 5 was controlled by a control section 32.

An image was formed in the following manner using the apparatus shown in FIG. 5 having the above-described configuration.

First, the thermal head 20 was energized in response to a cyan image signal, and at the same time, the fluorescent lamp 21 was irradiated in a negative direction. As shown in the timing chart in Figure 6, the irradiation time is 30m.
It was set to 5ec. After 10 m5 ec had elapsed after the end of the irradiation, as shown in FIG. 6, the thermal head 20 was energized in response to a magenta image signal, and --like light was irradiated from the fluorescent lamp 22. The current application time and irradiation time at this time were the same as in the case of cyan. Furthermore, the same process was carried out for the yellow image signal. 120 m sec / like this
The recording medium 1 is moved by a stepping motor (not shown) and a transfer roll 2 in synchronization with the repetition period of line.
5 and transported in the direction of arrow A. Next, the recording medium 1 is transferred from the cassette 3o through the guide pair 28 by the paper feed roller 29 and the conveyance roller 33.
After being superimposed on the PET sheet 24, the transfer roller 2
5 and the pressure roller 26. As this transfer roller 25, one made of an aluminum roller is used,
The built-in heater 34 lowers the surface temperature to 1
Heating was controlled to 20°C. In addition, the pressure roller 26
An aluminum roller coated with silicone rubber was used. The pressure contact force of the transfer roller 25 and the pressure roller 26 was set to 25 K g f / cm 2 .

Between the two wooden rollers 25 and 26 arranged in this way,
When the recording medium 1 on which the transferred image was formed and the OHP sheet 24 were passed over each other, the multicolor transfer image on the recording medium 1 was transferred onto the OHP PET sheet 24. The PET sheet 24 on which the intermediate transfer image is formed in this way is
The paper was discharged onto the paper discharge tray 31. The thus obtained multicolor image on the PET sheet 24 had no color shift, and was a clear, high-quality image with high saturation.

This OHP PUT sheet 24 is superimposed on low smoothness paper (bank bond paper, not shown) as a recording medium, and the transfer roller 25 and pressure roller 2 are heated to a surface temperature of 120°C.
When the paper was passed through the pressure feeding section No. 6, a clear multicolor image was transferred onto the bank bond paper at a high transfer rate of 95% or more. The maximum optical density of the transferred recorded image thus obtained on the bank bond paper was approximately 1.5.

As described above, in the image forming method of the present invention, an intermediate transfer medium is used, and when an image forming element is selectively transferred from a transfer recording medium to the intermediate transfer medium, the transfer recording medium Because a portion of the above binder is actively attached to the image forming element transferred to the intermediate transfer medium, selectivity in transferring the image forming element from the transfer recording medium to the intermediate transfer medium is improved. At the same time, the transfer rate of the image forming element from the intermediate transfer medium to the recording medium made of plain paper or the like is improved, making it possible to perform stable, high-quality recording on the recording medium, which is the final transfer medium. becomes.

[Brief explanation of the drawing]

Figures 1 to 3 are schematic cross-sectional views in the thickness direction of a recording medium for explaining the principle of multicolor recording in the present invention, and Figure 4 is a graph showing an example of the light absorption characteristics of the photoinitiator used in the present invention. 5 is a schematic sectional view of the apparatus used in the image forming method of the example, and FIG. 6 is a drive timing chart of each energy applying means used in the example. 1... Record #i medium, 1a... Distribution layer of image forming element, 1b... Binder layer, IC... Base material, 2... Image forming element, 3... Intermediate transfer medium, 4... Recorded object, 20... Thermal head, 20a to 20f... Heating resistor of thermal head, 21.22.23... Fluorescent lamp, 24... Intermediate transfer medium , 25... Transfer roller, 26... Pressure roller. ■1: Figure 1

Claims (1)

[Claims] Using a recording medium in which a binder layer and a distribution layer of image forming elements whose transfer characteristics change by applying light energy and thermal energy are sequentially provided on a base material; a transferred image forming step of forming a transferred image by applying light energy and thermal energy to the distribution layer under conditions of applying at least one type of energy among energy and thermal energy in accordance with recorded information; an intermediate transfer step in which the formed recording medium is brought into contact with an intermediate transfer medium and then separated to transfer the transferred image to the intermediate transfer medium; and a transfer recording step in which the image transferred to the intermediate transfer medium is transferred to a recording medium. forming an image, and maintaining the temperature of the recording medium above the softening point of the binder when separating the recording medium and the intermediate transfer medium in the intermediate transfer step. Image recording method.