JPH0365952A - Transfer recording medium - Google Patents

Abstract

PURPOSE:To improve the yield of microcapsules in the process for production of media by incorporating a positive chargeable yellow or magenta pigment into at least one kind of the internal phases of plural kinds of the microcapsules. CONSTITUTION:A recording layer 1a consists of plural kinds of the microcapsules formed by encapsulating the internal phases which contain at least a compd. having ethylenic unsatd. double bonds, a photopolymn. initiator and pigments and are solid at ordinary temp. The positive chargeable yellow or magenta pigment is incorporated into at least one kind of the internal phases of plural kinds of the microcapsules. The composition between the particles which arises at the time of producing the fine particles of the internal phases of the microcapsules is, therefore, suppressed to a low level. The yield of the capsules is improved in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transfer recording medium used in printers, copying machines, facsimiles, and the like.

[Background Art 1] In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods and devices suitable for each information processing system have also been developed and adopted. One such recording method is the thermal transfer recording method, which uses a lightweight, compact, and noiseless device.
It has excellent operability and maintainability, and has been widely used recently.

This thermal transfer recording method generally uses a thermal transfer medium formed by coating a sheet-like support with a thermal transfer ink made of a heat-melting binder and a colorant dispersed therein. The thermal transferable ink layer is superimposed on the transfer medium so as to be in contact with the transfer medium, and heat is supplied from the support side of the thermal transfer medium by a thermal head to transfer the melted ink layer to the transfer medium. A transfer ink image is formed on a medium according to the shape of heat supply. According to this method, plain paper can be used as the transfer medium.

[Problems to be Solved by the Invention] However, conventional thermal transfer recording methods are not without drawbacks. This is because in the conventional thermal transfer recording method, the transfer recording performance, that is, the print quality, is greatly affected by the surface smoothness.Good printing is performed on highly smooth transfer media, but on less smooth transfer media. In some cases, the print quality deteriorates significantly. However, even when using paper, which is the most typical transfer medium, highly smooth paper is rather special, and ordinary paper has various irregularities due to entangled fibers. Therefore, in the case of paper with large surface irregularities, the hot melted ink during printing cannot penetrate into the fibers of the paper and only adheres to the concavities on the surface or the vicinity thereof, resulting in the edges of the printed image not being sharp. or part of the image may be missing, resulting in a decrease in print quality.

In addition, with conventional thermal transfer recording methods, only one color image can be obtained with one transfer, so to obtain a multicolor image, it is necessary to repeat the transfer multiple times to overlap the colors. there were. However, it is very difficult to accurately superimpose images of different colors, and it is difficult to obtain images without color shift. In particular, when focusing on a single pixel, colors are rarely superimposed in a single pixel, and in the end, in conventional thermal transfer recording methods, multicolor images are created by aggregation of pixels with shifted colors. was forming. For this reason, clear multicolor images cannot be obtained using conventional thermal transfer recording methods.

In addition, when trying to obtain multicolor images using conventional thermal transfer recording methods, it is necessary to install multiple thermal heads or to make complicated movements such as reverse feeding and stopping of the transfer medium, which requires the entire device. This method has drawbacks such as large and complicated data and a decrease in recording speed.

Therefore, the present applicant has proposed that when a photothermal sensitive material is used and light energy and thermal energy are applied in response to an image signal, the reaction of the material rapidly progresses and the transfer characteristics irreversibly change, resulting in an image signal. He has invented an image forming method and a transfer recording medium for forming an image with the above-mentioned characteristics according to the difference in characteristics and transferring it to a recording medium, and has already filed an application (Japanese Patent Application Laid-Open No. 6-0-1).
50597).

In addition, the applicants have already filed a patent application for a combination of a phosphor that generates ultraviolet light in three wavelength ranges and a photopolymerization initiator with a corresponding photosensitive wavelength range to select the hue (patent application). (Sho 61-293157).

The transfer recording medium of the application can eliminate and improve the defects and drawbacks of the conventional heat-sensitive recording method, and the present invention further improves the transfer recording medium,
The object of the present invention is to provide a transfer recording medium capable of forming images of high quality and high sensitivity without fogging or white spots.

The present invention further improves the above transfer recording medium, and particularly provides a transfer recording medium that can improve the yield of microcapsules in the medium manufacturing process.

[Means for Solving the Problems] The present invention provides a transfer recording medium in which a recording layer whose transfer characteristics change upon application of heat and light energy is provided on a support, wherein the recording layer is at least ethylenically unsaturated. It consists of multiple types of microcapsules encapsulating an internal phase that is solid at room temperature and contains a compound having a double bond, a photopolymerization initiator, and a pigment, and at least one type of internal phase of the multiple types of microcapsules contains , a transfer recording medium characterized by containing a positively chargeable yellow or magenta pigment, and according to the structure of the medium, the aggregation between the particles that occurs when producing the fine particles of the internal phase of the microcapsules. As a result, the yield of capsules can be improved, and the generation of capsule particles with poor sensitivity and transfer characteristics caused by coalescence of particles can be reduced. High quality images can be formed.

The internal phase, which is used in the present invention and whose transfer characteristics change upon application of heat and light energy, contains at least a compound having an ethylenically unsaturated double bond, a photopolymerization initiator, and a pigment. It is composed of Generally, the internal phase is often solid at room temperature.

As a method for manufacturing microcapsules having such an internal phase, after forming solid particles of the internal phase, a wall material is formed by a complex coacervation method such as gelatin-gum arabic or an in-situ polymerization method such as urea-formalin. It is manufactured by forming.

The method for forming the solid particles includes preparing a solution in which a compound having an ethylenically unsaturated double bond, a photopolymerization initiator, a pigment, etc. are dissolved and dispersed in a solvent such as chloroform, and containing at least an anionic polymer compound. This can be carried out by a method such as emulsifying and dispersing in an aqueous solution to form a protective colloid, and then removing the solvent from the resulting emulsion to produce solid photosensitive microparticles. A transfer recording medium can be produced by encapsulating particles and supporting them on a support.

In the production of the solid particles, when removing the solvent from the emulsion, the compounds, photoinitiators, pigments, etc.
Hereinafter, these will be referred to as composition pillars. ) is dissolved and dispersed in the form of microparticles, and if the stability of the emulsion is poor, the particles will coalesce during desolvation, resulting in a decrease in the yield of microcapsules and a decrease in the yield of microcapsules obtained. The use of capsules may lead to deterioration of the characteristics of the recording medium.

As a result of intensive research into reducing the coalescence of microparticles caused by the instability of the emulsion, the present inventors discovered that the cause of instability was mainly due to the pigment used.
Furthermore, when we examined the production of the transfer recording medium using various pigments, we found that especially in yellow or magenta pigments, coalescence of particles is extremely severe, which may lead to a decrease in yield and deterioration of properties. . The reason for this is that yellow or magenta pigments are commonly used in Hansa Yellow, Benzine Yellow, Brilliant Carmino 6
It is considered that it is composed of pigments such as B and has particularly large negative chargeability. That is, in an emulsion in which an anionic polymer is dissolved to form a protective colloid, it is assumed that the pillars of the composition dissolved in the solvent will also be negatively charged if they contain the above pigment, and as a result, they will become hydrophobic colloids. It is thought that electrical stability cannot occur between the hydrophilic colloids and the stability of the emulsion deteriorates.

On the other hand, based on the present invention, the internal phase particles containing the positively chargeable pigment form positively charged stable microparticles in the negatively chargeable protective colloid agent, and since the microparticles are both positively charged, It is thought that coalescence is prevented by the repellency of the particles.

Based on the above viewpoint, the present inventors investigated the relationship between the chargeability of pigments and the stability of emulsions, and found that emulsions using positively chargeable yellow or magenta pigments were highly stable, leading to the present invention. It is.

The chargeability of the pigment can be measured by placing 1.0 g of the pigment and 99.0 g of the ferrite carrier in a bottle, stirring in a ball mill for 60 minutes, and then using a blow-off powder charge measuring device (Toshiba Chemical TB-200). .

The positively chargeable yellow or magenta pigment that can be used in the present invention is C, 1, Pig No. Y-17C, 1, No. 211
05 insoluble disazo pigment (yellow) C,1,Pig,No,R-48-I C,1,No
, 15865:1 Watch Young Red (Magenta) C, 1, Pig No., R-48-3C, 1, No. 15
865:3 Watch Young Red (Magenta) C,1,PigNo., R-122C,r, 73915 Quinacridone (Magenta), etc., but are not limited to yellow or Magenta can be used. Further, two or more types of the above pigments may be mixed, or a negatively chargeable pigment may be mixed if the entire internal phase exhibits positive chargeability.

Further, the positively chargeable yellow or magenta pigment has one hue among a plurality of hues. In other words, in the present invention, the fact that at least one internal phase of the plurality of types of microcapsules contains positively charged yellow or magenta means that the microcapsules consisting of a plurality of hues develop yellow and/or magenta hues. This means that the pigment is contained in the internal phase of one or both of the microcapsules.

In the present invention, the content of the positively chargeable pigment may be about the same as that of the yellow or magenta pigment used in -i, but usually solid particles used in the microcapsules that develop the hue. 3 to 30% by weight higher than that.

Other configurations of the present invention will be described in detail below.

In the transfer recording medium of the present invention, the microcapsules supported on the support are composed of multiple types of capsules, and if each capsule has a different photosensitive wavelength range and a different hue, a full-color image can be formed. becomes possible.

In order to make it easier to understand, in the following explanation, microcapsules are divided into 3 elementary bodies (A), CB), and (c).
seeds, and the sensitive wavelength range of these capsules is (A)
300-360nm, (B) 360-430nm,
(C) Explanation will be given assuming that the wavelength is 430 nm or more. The positively chargeable yellow or magenta pigment according to the present invention is an element body (A).
or equivalent to (C).

The photopolymerization initiators used in the present invention include those with maximum absorption of 300 to 360 nm, including benzyl, 4.
Diketone compounds such as 4'-dimethoxybenzyl, 4.4'-dimethylbenzyl, 4.4'-dihydroxybenzyl, and those with an absorption maximum of 360 to 430 nm, such as thioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, 2.4- Thioxanthone derivatives such as diethylthioxanthone and 2,4-diisopropylthioxanthone, and those having an absorption maximum of 430 nm or more, such as 7-diethylamino-3,3'-carbonylvistamarin, 3,3'-carbonylbis(7-dinithylaminocoumarin) Although a composite initiator of a coumarin derivative such as ) and an S-triazine derivative or camphorquinone is used, the present invention is not limited to the above initiators.

The polymerizable compound having an ethylenically unsaturated double bond in the base bodies (A), (B), and (C) is:
A compound that has at least one ethylenically unsaturated double bond in its chemical structure, and has chemical forms such as monomers, oligomers, and polymers.

Examples include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and ethylene glycol, triethylene glycol, tetraethylene glycol, trimethylolpropane, and 1,3-butanediol. , esters with aliphatic polyhydric polyol compounds such as pentaerythritol and dipentaerythritol, and alcohols containing polyisocyanates (which may be reacted with polyols as necessary) and ethylenically unsaturated double bonds; Urethane acrylates synthesized by polyaddition reaction of amines,
Examples include urethane methacrylates, epoxy acrylates synthesized by an addition reaction between an epoxy resin and acrylic acid or methacrylic acid, polyester acrylates, and spin acrylates.

In addition, as a polymer, the main chain has a skeleton of polyalkyl, polyether, polyester, polyurethane, etc., and the side chain has an acrylic group, a methacrylic group, a cinnamoyl group, a cinnamylideneacetyl group, a furyl acryloyl group, etc. The present invention is not limited to these examples, but the present invention is not limited thereto.

Further, element bodies (A) and (B) containing the above-mentioned photopolymerization initiator and a polymerizable compound having an unsaturated double bond.

(C) may further contain known additives such as binders, UV absorbers, plasticizers, and thermal polymerization inhibitors, if necessary.

As the binder, any organic polymer that is compatible with monomers, oligomers, or polymers having unsaturated double bonds may be used. 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 chlorinated polyethylene and chlorinated polyethylene. Examples include chlorinated polyolefins such as polypropylene, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, or copolymers thereof, as well as polyvinyl alkyl ether, polyethylene, polypropylene, polystyrene polyamide, polyurethane, chlorinated rubber, and cellulose derivatives. However, the present invention is not limited thereto.

These polymers may be used alone or in a mixture of two or more in an appropriate ratio. Furthermore, waxes may be used as binders, regardless of whether they are compatible or incompatible. Any amount of these polymers can be mixed into the total composition.

Further, in the present invention, anionic polymer compounds that can be used for emulsification when manufacturing solid particles of the internal phase include natural semi-synthetic polymer compounds such as gum arabic, pectin, casein, and xanthan gum, poly(meth) acrylic acid,
(meth)acrylic acid copolymer ((meth)acrylic acid-(
(meth)acrylic acid alkyl ester), maleic anhydride copolymer (styrene-maleic anhydride copolymer, imbutylene-maleic anhydride copolymer, methyl vinyl ether-maleic anhydride copolymer, ethylene-maleic anhydride copolymer) synthetic polymers such as polystyrene sulfonic acid, acrylamide copolymers (acrylamide-acrylic acid copolymers, etc.), and the like.

Next, the elementary bodies (A), (B), consisting of the above-mentioned components,
(C) can be used as a particulate element having a particle size of about 3 to 50 μm, preferably 7 to 15 μm when solid;
, (B).

Even if (C) is liquid or solid, the particle size is about 3 to about 50
A recording medium is prepared by physically and chemically bonding the microcapsules to a support as microcapsules having a size of 7 to 15 μm. The average particle size of the elements (A), (B), and (C) is preferably about 10 μm. When the microcapsules are bound onto the support using an adhesive, the binder is preferably an epoxy adhesive, a polyester adhesive, a urethane adhesive, an acrylic adhesive, a urethane acrylic adhesive, an ethylene-vinyl acetate copolymer adhesive, or the like. used.

Next, a specific example of an image forming method using the recording medium of the present invention will be shown based on FIG. First, the transfer recording medium 1 is stacked on the heating resistor array 20 of the thermal head, and light is irradiated so as to cover the entire area of the heating section of the thermal head. The light to be irradiated is the image forming element (A).

The wavelengths at which (B) and (C) react are sequentially irradiated.

For example, image forming elements (A), (B), (C)
If it is colored magenta, cyan, or yellow, the wavelength destination (M), λ (C), and light ((Y)) are sequentially irradiated.

That is, first, light of a different wavelength (M) is irradiated from the transfer recording layer 1a side of the transfer recording medium 1, and the heating resistors 20b and 20c of the thermal head, for example, are caused to generate heat. Then, among the image forming elements containing the magenta coloring material, the image forming elements to which both heat and light of wavelength L (M) were applied (the hatched part in Figure 1a), hereinafter referred to as the cured The image forming element (indicated by hatching) is cured.

Next, as shown in FIG. 1b, the transfer recording layer 1a is coated with a wavelength λ(
While irradiating the light of C), the heating resistors 20a, 20
When b and 20c generate heat, among the image forming elements containing the cyan coloring material, the image forming element to which heat and light of wavelength λ(C) have been applied is cured.

Furthermore, as shown in FIG. 1c, when light of wavelength L (Y) is irradiated and the heating resistors 20c and 20d are made to generate heat, the heat and wavelength 'A' of the image forming element containing the yellow coloring material are emitted. The image forming element to which the light of (y) is applied is cured, and a transfer image is finally formed on the transfer recording layer l by the image forming element that has not been cured. This transferred image is transferred to the transfer medium 21 in the next transfer process as shown in FIG. 1d.

In the transfer process, the transfer recording medium on which the transferred image has been formed is brought into contact with the transfer medium, and the transferred image is selectively transferred to the transfer medium by heating from the transfer recording medium or the transfer medium side to form an image. do. Therefore, the heating temperature at this time is determined so that only the transferred image is selectively transferred in the transfer step. Further, in order to perform the transfer efficiently, it is also effective to apply pressure at the same time. Pressure is particularly effective when using a transfer medium with low surface smoothness. Furthermore, if the physical property that governs the transfer characteristics is the viscosity at room temperature, transfer is possible only by applying pressure.

Further, heating in the transfer process is suitable for obtaining a durable multicolor image that is stable and has excellent storage stability.

In the example explained above in FIGS. 1a to 1d, a method is shown in which an image is formed by irradiating light onto the entire area of the heating resistor row 20 of the thermal head and selectively causing the heating resistors of the thermal head to generate heat. However, by uniformly heating a certain part of the transfer recording medium (in terms of the thermal head shown in Fig. 1a,
In the case where all the heating resistors generate heat), a multicolor image can be similarly formed by selectively irradiating light. That is, light energy of a wavelength that is modulated according to the recording signal and that is selected depending on the color tone of the image forming element whose physical properties governing the transfer characteristics are desired to be changed is applied together with thermal energy.

A preferred example of a recording apparatus using the recording medium of the present invention will be explained using FIGS. 2(A) and 2(B).

In the figure, reference numeral 1 denotes a transfer recording medium of the present invention in the form of a long sheet, which is wound into a roll and is removably incorporated into an apparatus main body M as a supply roll 2. That is, this supply roll 2 is removably loaded onto a rotatable shaft 2a provided in the main body M of the apparatus.

First, the leading edge of this transfer recording medium l is placed on the supply roll 2.
Transfer roller 4a and pressure roller 4 pass through guide roller 12a, thermal head 3a and guide roller 12b.
Peeling roller 5, guide rollers 12c and 1 from between b
2d to reach the take-up roll 6, and its tip is locked to the take-up roll 6 by means such as a gripper (not shown). Thereafter, while applying torque to the winding roll 6 in the direction of arrow C using a known drive means,
By rotating the transfer roller 4a, the transfer recording medium 1 is fed out in the direction of the arrow a, and is sequentially wound around the circumferential surface of the take-up roll 6.

Note that during the winding, a certain back tension is applied to the supply roll 2 by, for example, a hysteresis brake (not shown), and this tension and the guide rollers 12a and 12b cause the transfer recording medium 1 to move toward the thermal head 3a. It is configured to be conveyed while being pressed against the object at a certain pressure and at a certain angle.

The recording section is composed of a heating means for applying thermal energy to the recording medium 1 and a light irradiation means for applying light energy to the transfer recording medium 1 as well.

The heating means generates heat on the surface of the thermal head 3a according to the image signal, for example, with a width of 0.2 mm and a dot of 8 dots/mm.
A-4 size, line type heating resistor rows 20 are arranged, and as described above, the support lb side of the transfer recording medium 1 is pressed against the heating resistor row 20 with a predetermined pressure by pack tension during conveyance. is configured to do so. Note that the above-mentioned signals are emitted from a control unit of a facsimile, an image scanner, an electronic blackboard, etc., depending on the purpose.

On the other hand, the transfer recording layer l facing the thermal head 3a
A light irradiation means is provided on the a side. As the light irradiation means, the light emitting wavelength ranges are different from each other, and the element body (A),
Three fluorescent lamps capable of reacting (B) and (C) individually, for example, Toshiba FL10A70
E35/33T15 (peak wavelength 335r+m)
, Toshiba FLIOA70E39/33T15 (peak wavelength 390 nm), Toshiba FL10A70B/33
T15 (peak wavelength 450 nm) or the like may be used, but as shown in FIG. 2(b), a glass with a thickness of 2 mm (manufactured by 5CHOTT, West Germany, The rotating body 3C made of a cylinder made of DURAN 50) has three pairs of rollers 3d, 3e, 3.
The roller 3d may be rotatably supported by a roller 3d, and rotated at a constant speed by driving and rotating the roller 3d by a motor.

Three types of phosphors 100, 1 are provided on the inner surface of the rotating body 3c.
01 and 102 are coated at 120 degrees (three equal parts) in the cylindrical direction, and these phosphors are irradiated by light from a light source 3g (for example, Toshiba germicidal lamp GL-20) disposed inside the rotating body 3c. When excited, it emits fluorescence.

The peak wavelengths of the light from phosphors 100, 101, and 102 are 300 to 360n+n and 360 to 430nm, respectively.
, in the range of 430 to 600 nm, and the half width thereof must be as small as possible in order to suppress crosstalk.

As the phosphor 100 having a peak wavelength in the wavelength range of 300 to 360 nm, thallium-activated calcium phosphate (
Ca (PO4)
4) Preferably, the main component is a: T-do). These fluorescent materials have high luminescence intensity and are very preferable.

As the phosphor 101 having a peak wavelength in the wavelength range of 360 to 430 nm, europium-activated strontium magnesium birophosphate (Sr, Mg) aPiT is used.

Those containing Eu) as a main component are preferred.

As the phosphor 102 having a peak wavelength in the wavelength range of 430 to 600 nm, europium activated barium magnesium aluminate (Ba, MgAl+eOty HE
Those containing u) as a main component are preferred.

As can be seen in Figure 4, each phosphor 100.101.10
The peak wavelengths of 2 are within the range of 300 to 360 nm+, 360 to 430 nm, and 430 to 600 nm, respectively.
Exists within the range of m. For example, thallium-activated calcium nonate is at 335 nm (Graph 100), europium-activated strontium magnesium birophosphate is at 395 nm (Graph 101), and europium-activated barium magnesium aluminate is at 453 nm.
Each has a peak wavelength at m.

In addition to the above materials, binders and other additives may be mixed with the phosphor 100.101.102, but at least 90% by weight based on the weight of each of the phosphor lot, lot, and 1.02. is preferably occupied by the above-mentioned fluorescent material.

〔Example〕

Example 1 50 g of a 30% chloroform solution of the ingredients shown in Table 1 was microencapsulated by the method shown below.

Method for manufacturing macrocapsules: 100 g of water and 26 g of an aqueous NaOH solution (polymer concentration 20.6%) of isobutylene-maleic anhydride copolymer (Kureha Chemical Co., Ltd.: Isoban-10) were mixed, and 3.1 g of pectin was added thereto. and stirred for 20 minutes.

The pH was then adjusted to 4.0 with a 20% sulfuric acid solution.

While stirring at 300 rpm with a homomixer shown in Table 1, a solution prepared by dissolving 20 g of the components shown in Table 1 in 40 g of chloroform was added over 10 to 15 seconds, and emulsification was continued for 10 minutes. The emulsion was transferred to a beaker at 500 m°C, the liquid temperature was raised to 50°C, and the solvent was removed by stirring with a stirring blade. The emulsion was poured into 0°C water and 1°C, and after stirring for a while, 3
The combined components were removed using a 00 mesh sieve, and then filtered using a Nuche filter, and the resulting particles were heated at 40°C.
It was dried in a smooth dryer at a temperature of .

The weight of the obtained core (internal phase) was 12.5 g, and the yield based on the amount charged was 83%.

Example 2 Core particles were prepared in the same manner as in Example 1 by changing only the pigments among the components shown in Table 1 to the pigments shown in Table 2, and the yield when each pigment was used was determined. Ta. Second result
Shown in the table. In addition, the amount of charge of the pigment is written as is from the catalog value of Dainippon Ink Co., Ltd.

As can be seen from Table 2, it can be seen that the chargeability of the pigment is negative, and the larger the chargeability value is, the lower the yield of core particles is.

Table 2 Example 3 Core particles were prepared using the same ingredients as in Example 1 using the ingredients shown in Table 3.4.5. 10g of the prepared particles were each
After dispersing in 0g of water, 6g of urea was added to make 0.0g of water. The pH was brought to 4 with IN sulfuric acid solution. Then, after adding Log formalin and stirring at room temperature for 10 hours, the pH was adjusted to 2 and the reaction was carried out at a temperature of 50° C. for 2 hours. The reaction solution was reduced to 0. I
Return to neutrality with N sodium hydroxide solution, 1000
After washing by pouring into mj2 water, filtration and drying were performed.

After mixing three types of microcapsules at the same weight, a transfer recording medium was produced by the method described below.

Table 5 Thermoplastic polyester (Nippon Gosei Kagaku Kogyo, Polyester-011) was diluted with toluene and applied to a thickness of 0.5 μm on a PET (polyethylene terephthalate) film (6 μm thick) using an applicator. Next, the element (A) was sprinkled onto the film and spread, and unbound particles were shaken off. The film was made of P with a thickness of 100 μm and 50 μm.
Sandwiched with ET film, temperature 110℃, pressure 2-3 kg
/cm'' heat roller, the PET film was peeled off, and a transfer recording medium was prepared in which the element body (A) was firmly adhered to the PET film. Similarly, the element body (B
) (C), and the elementary bodies (A) , (B) , (C)
A transfer recording medium was prepared by mixing equal amounts of the following.

The transfer recording medium consisting of the element body (A) was wound into a roll and incorporated into the apparatus shown in FIG. The thermal head used was an A-4 size line type with a width of 2 mm and 8 dots/mm, in which rows of heating elements were arranged at the edges.

As a light source, a glass tube was coated with thallium-activated calcium phosphate, europium-activated strontium magnesium birophosphate, and europium-activated barium magnesium aluminate, each at a 120-degree angle. It was used.

Subsequently, the transfer recording medium was wound in the apparatus, and when the thermal head and the excitation light source were energized at the timing shown in FIG. 5, a good high-quality multicolor image could be formed.

〔Effect of the invention〕

As explained above, according to the present invention, if the internal phase of the microcapsules is prepared using a positively charged yellow or magenta pigment, coalescence between particles during solvent removal can be suppressed to a low level. , core yield is improved and costs can be significantly reduced.

Furthermore, since there are fewer coalesced particles, the probability of the existence of particles with poor sensitivity and transfer characteristics is low, and high-quality images with less fogging and white spots can be formed.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle by which multicolor recording is possible using the transfer recording medium according to the present invention. FIGS. 2A and 2B are diagrams showing an example of an apparatus for performing multicolor recording using a transfer recording medium according to the present invention. FIG. 3 is a diagram showing the relationship between wavelength and transmittance of a light source that can be used in the present invention, that is, a quartz tube carrying a phosphor. FIG. 4 is a graph showing an example of the light emission characteristics of the phosphor. FIG. 5 is a diagram showing a timing chart of signals applied to the light source and the thermal head in Example 3. DESCRIPTION OF SYMBOLS 1... Transfer recording body, 1a... Transfer recording layer, 1b... Support body, 2... Supply roll, 2a... Shaft, 3a... Thermal head, 3c... Rotation body, 3dNf...roller pair, 3g...light source, 4a...transfer roller, 4b...pressure roller, 5...peeling roller, 6...take-up roll, 12aNd... - Guide roller, 20... Heating resistor array, 20a--d... Heating resistor, 100, 101.102... Fluorescent material, M... Main body.

Claims (1)

[Claims] In a transfer recording medium in which a recording layer whose transfer characteristics change upon application of heat and light energy is provided on a support,
The recording layer is composed of a plurality of types of microcapsules encapsulating an internal phase that is solid at room temperature and contains at least a compound having an ethylenically unsaturated double bond, a photopolymerization initiator, and a pigment. A transfer recording medium characterized in that at least one type of internal phase of the microcapsules contains a positively chargeable yellow or magenta pigment.