JPH03294859A - Transfer recording medium - Google Patents

Abstract

PURPOSE:To form multicolor images which have a high sensitivity, less fogging and good wavelength selectivity and do not generate white voids by using at least two kinds of microcapsules having the wall materials of the microcapsules having different absorption characteristics to UV light as a recording layer. CONSTITUTION:The recording layer on a base consists of plural kinds of the microcapsules, the transfer characteristics of which are changed by the impartation of heat and light energy. Plural kinds of the microcapsules are constituted of the internal phase contg. compds. having ethylenic ungate double bonds, respectively different photopolymn. initiators and coloring agents and the wall materials varying in the absorption characteristics to the UV rays. The multicolor images which have the high grade and high sensitivity and are decreased in the fogging and white voids are formed 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.

[Conventional technology]

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. As one such recording method, the thermal transfer recording method has recently been widely used because the apparatus used is lightweight, compact, noiseless, and has excellent operability and maintainability. 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 the medium in accordance with the shape of heat supply.

According to this method, plain paper can be used as the transfer medium.

[Problem 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.

The present applicant uses a photothermal sensitive material, and when light energy and thermal energy are applied in accordance with the image signal, the reaction of the material rapidly progresses and the transfer characteristics irreversibly change, causing the image signal to change. He has invented an image forming method and a transfer recording medium for forming an image according to the above characteristics and transferring it to a recording medium, and has already filed a patent application (Patent Application No. 6O-1505).
97).

The transfer recording medium of the application can eliminate and improve the problems and drawbacks of the conventional thermal recording method as described above, and the present invention is a further improvement of the transfer recording medium, which has high quality and The main objective is to provide a transfer recording medium capable of forming multicolor images with high sensitivity and less fogging and white spots.

[Means to solve the problem]

In the present invention, the recording layer of the support t is composed of a plurality of types of microcapsules whose transfer characteristics change upon application of heat and light energy, and the plurality of types of microcapsules are composed of a compound having an ethylenically unsaturated double bond. and an internal phase each containing at least a different photoinitiator and a colorant;
and a transfer recording medium comprising wall materials each having different absorption characteristics for ultraviolet rays,
According to the transfer recording medium, it is possible to form a transferred image with high sensitivity and good transferability, and particularly good gradation.

In the present invention, the microcapsule is composed of a capsule wall and an internal phase, and the internal phase is composed of at least a compound having an ethylenically unsaturated double bond, a photopolymerization initiator, and a coloring agent, and the microcapsule is formed by applying heat and light energy. The transfer characteristics change, and multiple types of microcapsules are
The photopolymerization initiator contained in the internal phase of the microcapsules has a plurality of photosensitive wavelength ranges, that is, two or more types of microcapsules exhibit different hues. Furthermore, in the present invention, wall materials having different absorption characteristics for ultraviolet rays refer to wall materials that contain a photopolymerization initiator that is sensitive to ultraviolet rays of a relatively low wavelength among the photopolymerization initiators that have the above-mentioned photosensitive wavelength ranges. The wall material of the capsule containing an internal phase containing a photopolymerization initiator that is sensitive to relatively high wavelengths of ultraviolet light is This means that the transmittance of

In the present invention, ultraviolet light refers to light in the wavelength range of 200 to 600J1m, but in general, it is desirable that the wavelength range of the light that sensitizes the photopolymerization initiator used is divided into the range of approximately 300 to 600N11, and the transmittance is In particular, it refers to the transmittance of ultraviolet light in this range. This is because many photoinitiators contain an aromatic ring within their molecules, and the aromatic ring π→π*
Since the absorption band based on transition exists below 300 nm, 30
All of them are sensitive to light with a wavelength of 0 nm or less, making it difficult to separate the sensitive wavelength range.
This is because it becomes difficult to obtain sufficient sensitivity with light having a wavelength of 0r+m or more.

The recording medium of the present invention is intended for recording in at least two colors, and has photosensitive characteristics in two or more wavelength ranges by dividing the wavelength range of 300 to 600 nm into at least two wavelength ranges. It is constructed by supporting microcapsules each exhibiting a different hue on a support.

The present invention can be applied to multi-color or full-color recording using two or more colors, and will be described below using two-color recording as an example.

A recording medium is prepared by supporting two types of microcapsules A and B, which have different photosensitive wavelength ranges and exhibit different hues, on a support. Here, when printing in hue B, if the recording medium is heated and irradiated with light in the photosensitive wavelength range of microcapsules A, the microcapsules will harden and lose their transfer characteristics, so the recording medium will be heated. When the recording paper is passed through a heating and pressing means such as a beat roller facing the transfer paper, B
The hue of the image can be recorded. Furthermore, when recording hue A, light in the B photosensitive wavelength range may be irradiated in the same manner. At this time, it is difficult to completely divide the photosensitive wavelength range of microcapsules A and H, so when microcapsules A and H are irradiated with the corresponding light, microcapsules B will also react to some extent, resulting in an outstanding image. occurs.

As a result of intensive study by the present inventors to solve the above problems,
The inventors discovered that it is possible to increase the wavelength selectivity of the microcapsule wall material by adding a substance that absorbs light outside the wavelength range to which the internal phase is sensitive, leading to the present invention.

As one means, it is naturally possible to adjust the absorption characteristics of ultraviolet light by applying completely different wall materials to two or more types of microcapsules, and this achieves the object of the present invention. However, the powder characteristics of each capsule change, and the encapsulation process must be performed separately for each capsule, which is not without practical problems. Therefore, the present inventors easily solved the above problems by using urea-formalin or urea-melamine resin as the main component and introducing an aromatic ring having a hydroxyl group into the resin. This led to the realization of a transfer recording medium.

For example, if a wall material is formed from a ternary system of urea-formalin-dihydroxynaphthalene for an internal phase containing a photopolymerization initiator that is sensitive to relatively long wavelengths,
Since the absorption of the naphthalene ring ranges from 300 to 350 rv+, the sensitivity of the capsule to short wavelength light (wavelength region of 350 nm or less) is further reduced. If the wall material containing the microcapsules is formed of only urea-formalin, the sensitivity of the microcapsules to short wavelength light will not decrease, and wavelength selectivity can be improved as a result.

In other words, in the wall material of a capsule that contains an aromatic ring of an aromatic compound, the wall material absorbs short wavelength light and acts as a filter, so it is not included in the photopolymerization initiator in the internal phase. It is possible to reduce the amount of short wavelength light that reaches and is absorbed by the aromatic ring, and the curing reaction can be suppressed. By selecting a compound having an aromatic ring to be introduced into the urea-formalin resin or melamine-formalin resin, which is the main component of the wall material, in accordance with the sensitive wavelength range of the photopolymerization initiator contained in the internal phase, the desired This makes it possible to impart wavelength selectivity to microcapsules.

In order to perform the above action, the aromatic ring is preferably contained in the range of about 0.1 to 30 wt% in the constituent molecules of the resin, and depending on the type of aromatic compound used and the amount of the aromatic ring introduced, Desired light absorption characteristics can be achieved. That is, the more aromatic rings are introduced, the greater the absorption at short wavelengths.

In the present invention, the absorption of the shell agent is an auxiliary means to enhance the spectral properties of multiple types of capsules, and the main spectral properties are determined by the photoinitiator contained within the capsules.

This is because the absorption of the compound introduced into the shell agent becomes broad due to the encapsulation reaction. Therefore, the absorption wavelength of the shell agent cannot be precisely controlled, and the method described below is effective.

That is, by combining a shell agent with a benzene ring and a shell agent without a benzene ring, a capsule consisting of a shell that absorbs light of 350 nm or less and a shell that does not are prepared. By using benzene, naphthalene, anthracene, etc. as the aromatic compound introduced into the absorbing shell, absorption can be extended to longer wavelengths.

On the other hand, since the shell that does not contain an aromatic ring is formed from urea and formalin, it can maintain high transparency even to light of 200 to 250 nm.

Further, the aromatic ring preferably has a hydroxyl group, so that it takes 1n-s to introduce the aromatic ring into the wall material.
This can be easily done using the IT, U II method, etc. In other words, due to the hydroxyl group attached to the aromatic ring, formalin reacts with the aromatic ring, the aromatic ring reacts, and a methylolated product of the aromatic compound is produced, and it reacts with urea or melamine, forming an aromatic ring in the resin. can be introduced.

As mentioned above, urea-formalin or melamine-formalin resin can be mentioned as the main component of the wall material of the microcapsules that can be used in the present invention.

Aromatic compounds having a hydroxyl group to be introduced here include α- or β-naphthol, dihydroxynaphthalene, hydroxyanthracene, 2,4-dihydroxyhensiphenone, 2-hydroxy-4-methoxy-
Benzophenone compounds such as 5-sulfohensephenone and benzotriazole compounds such as 2-(2°-hydroxy-5′-methylphenyl)hensitriazole can be used. Among these compounds, those which are sparingly soluble in water may be made soluble by methylolization with formalin in a polar solvent such as alcohol, if necessary.

Next, each structure of the internal phase of the microcapsule according to the present invention will be explained.

As the photopolymerization initiator contained in the internal phase in the present invention, any generally known compound that generates radicals when exposed to light can be used. For example, carbonyl compounds (
Benzoin compounds such as benzoin methyl ether,
Benzyl compounds such as anisyl and benzyl dimethyl ketal, quinone compounds such as anthraquinone and camphorquinone, thioxanthone compounds such as 2-chlorothioxanthone), azo compounds (azo compounds such as azobisisobutyronitrile, etc.) diazonium compounds such as enyldiazonium salts), organic sulfur compounds (sulfide compounds such as tetramethylthiuram monosulfide), halogen compounds (silver halide compounds such as silver bromide, carbon tetrachloride, quinolinesulfonyl chloride, etc.) Examples include halogen compounds, etc.), organometallic compounds (ferrocene, etc.), metal carbonyl compounds (manganese sulfonyl compounds, etc.), and photosensitive dyes (eosin, lifoflavin, cyanine dyes, etc.).

In addition, these photoinitiators can be used in combination with various sensitizers, such as amines (aliphatic amines such as triethanolamine, aromatic sensitizers such as ethyl-p-dimethylaminohenzoate). group amines, cyclic amines such as piperazine, etc.), ureas (diphenylurea, etc.),
Sulfur compounds (such as sodium diethyldithiophosphate), nitriles (such as dimethylaminohenzonitrile), phosphorus compounds (such as trilobylphosphine)
, chlorine compounds (such as hexachloroethane), pigments (
Cyanine dye, rose bengal, etc.) are used depending on the purpose.

These photopolymerization initiators are 2N! There are various combinations of dividing into the above sensitive wavelength ranges, but for illustrative purposes, 300~
When divided into two types, 360 nm and 360-600 nm, initiators for 300-360 nm include penzyl,
Diketone compounds such as 4,4°-dimethoxybenzyl, 4.4-dimethylbenzyl, and 4.4-dihydroxybenzyl, and those with an absorption maximum of 360 to 600 nm such as thioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, and 2.4-diethyl. Although thioxanthone derivatives such as thioxanthone and 2,4-diisopropylthioxanthone can be used, the present invention is not limited to the above-mentioned initiators and may be appropriately selected according to the desired wavelength range. Usually, the content of the photopolymerization initiator may be 0.1 to 10 parts by weight per 100 parts by weight of the internal phase.

Next, examples of polymerizable compounds containing an ethylenically unsaturated double bond in the internal phase include compounds having at least one ethylenically unsaturated double bond in their chemical structure, such as monomers, oligomers, Any material having a chemical form such as a polymer may be used. Examples include monomers such as methyl acrylate, methyl methacrylate, acrylonitrile, and acrylamide; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, and maleic acid; and ethylene glycol and triethylene. Esters with aliphatic polyhydric polyol compounds such as glycol, tetraethylene glycol, trimethylolpropane, 1,3-butanediol, pentaerythritol, dipentaerythritol, and polyisocyanates (reacted with polyols as necessary) Urethane acrylates and urethane methacrylates are synthesized by the polyaddition reaction of alcohols and amines containing ethylenically unsaturated double bonds, and urethane methacrylates are synthesized by the addition reaction of epoxy resins and acrylic acid or methacrylic acid. Examples include epoxy acrylates, polyester acrylates, and spin acrylates.

In addition, the polymer has a backbone of polyalkyl, polyether, polyester, polyurethane, etc. in the main chain, and polymers such as acrylic group, methacrylic group, cinnamoyl group, cinnamylideneacetyl group, furyl acryloyl group, etc. on the side 61. Examples include those into which reactive and crosslinking reactive groups are introduced, but the present invention is not limited to stiff materials. Usually, the amount of the compound having an ethylenically unsaturated double bond may be about 50 to 95 parts by weight per 100 parts by weight of the internal phase.

In addition, the internal phase containing the above-mentioned photopolymerization initiator and a polymerizable compound having an unsaturated double bond may further contain known additives such as binders, UV absorbers, plasticizers, and thermal polymerization inhibitors as necessary. can be contained.

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, methacrylic acid copolymers, and acrylic. Acid copolymers, maleic acid copolymers, chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, or copolymers thereof, as well as polyvinyl alkyl ether, polyethylene, and polypropylene. , polystyrene, polyamide, polyurethane, chlorinated rubber, cellulose derivatives, polyvinyl alcohol, polyvinylpyrrolidone, etc., but the present invention is not limited thereto. Typically, the binder is present in an amount of 5 to 40 parts by weight per 100 parts by weight of the internal phase.

The colorant is a component that is included to form an optically recognizable image, and various pigments and dyes are used as appropriate. Examples of such pigments and dyes include carbon black, yellow lead, molybdenum red, inorganic pigments such as Henkara, Hansa Yellow, Benzine Yellow, Brilliant Carmine 6B, Lake Red F5R, Phthalocyanine Blue, Victoria Blue Lake, and Fast Sky Blue. and colorants such as leuco dyes and phthalocyanine dyes. Usually, the colorant is present in amounts of 1 to 30 parts by weight per 100 parts by weight of the internal phase.

With the above configuration, microcapsules can be produced by the internal phase granulation process, encapsulation process, and recovery process described below.

In the granulation step, solid particles can be obtained by first emulsifying a solution containing the components of the internal phase in water containing a protective colloid and removing the solvent. After washing and filtering the particles, encapsulation is performed.

In the encapsulation step, the components forming the shell agent are dissolved in the water in which the internal phase particles are expanded, and the P of the water is dissolved.
When H is set to a predetermined value, the dissolved components undergo a polycondensation reaction and become insoluble in water, forming a shell on the core surface.

The prepared capsules are washed, filtered, dried, and classified to obtain a desired particle size distribution.

Through the above steps, microcapsules can be easily obtained.

In other words, the ultraviolet absorption characteristics of the wall material can be adjusted simply by introducing the aromatic ring without changing the main constituent components of the wall material, and since the aromatic ring has a hydroxyl group, it can be easily introduced. It can be done, and the practical benefits are great.

Next, the particle size of the microcapsules made of the above-mentioned ingredients is about 3 to about 50 μm, preferably about 7 to 15 μm,
A recording medium can be obtained by physically and chemically binding the microcapsules onto a support. The average particle diameter of the microcapsules is preferably about 10 μm. When binding microcapsules onto a support using an adhesive,
As the binder, epoxy adhesive, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, polyester, urethane, acrylic, urethane-acrylic, ethylene-vinyl acetate copolymer adhesive, etc. are preferably used.

Next, a specific example of an image forming method using the recording medium of the present invention will be shown based on FIG. For ease of understanding, it is assumed that the recording layer is composed of two types of microcapsules (A) and (B). First, the transfer recording medium 1 is stacked on the heating resistor 20 of the thermal head, and light is irradiated so as to cover the entire heated portion of the thermal head. The irradiated light has a wavelength that causes the microcapsules (A) and (B) to react in sequence. For example, microcapsules (A), (B
) is colored either magenta or cyan, the light of wavelengths λ(M) and λ(C) is sequentially irradiated.

That is, first, light of wavelength λ(M) is irradiated from the transfer recording layer 1a side of the transfer recording medium 1, and the heating resistors 20a and 20b of the thermal head, for example.

20c generates heat. Among the microcapsules containing a magenta coloring material, the microcapsules to which both heat and light of wavelength λ(M) were applied (the hatched part in Figure 1a. Hereinafter, the hardened microcapsules are hatched) ) is hardened. Next, as shown in FIG. 1b, when the transfer recording layer 1a is irradiated with light of wavelength λ(C) and the heating resistors 20c and 20d are made to generate heat, among the microcapsules containing the cyan coloring material, The microcapsules are cured by applying heat and light of wavelength λ(C). This transferred image is transferred to the transfer medium 21 in the next transfer step as shown in FIG. 1c.

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, heating during the transfer process is suitable for obtaining stable, durable, and durable multicolor images. Figures 1a to 1
In the embodiment explained in Fig. C, a method is shown in which an image is formed by irradiating light over the entire area of the heating resistor row 20 of the thermal head to selectively generate heat from the heating resistors of the thermal head. Heating a certain part of the medium uniformly (1a)
In the case of the thermal head shown in the figure, when all 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 microcapsules whose physical properties governing the transfer characteristics are desired to be changed is applied together with thermal energy.

A preferred embodiment of a recording apparatus using the recording medium of the present invention will be described with reference to FIG.

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 connected to a rotatable shaft 2 provided in the device main body M.
It is removably loaded into a.

Therefore, first, the leading edge of this transfer recording medium 1 is transferred to the supply roll 2.
Transfer roller 4a and pressure roller 4b pass through guide roller 12a, thermal head 3a and guide roller 12b.
From between the peeling roller 5 and the guide rollers 12c and 12d.
The winding roller 6 is directed to the winding roll 6, and its tip is locked to the winding roll 6 by means such as a gripper (not shown). Thereafter, by rotating the transfer roller 4a while applying torque to the take-up roll 6 in the direction of arrow C using a known drive means, the transfer recording medium 1 is rotated.
is edged out in the direction of arrow a, and is sequentially wound around the circumferential surface of the winding roll 6.

Incidentally, during the winding, a constant pack tension is applied to the supply roll 2 by, for example, a bisteresis 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. It is configured to be conveyed while being in pressure contact with 3a at a constant pressure and at a constant 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 is, for example, A-4 with a width of 0.2 cm and 8 dots/mm, which generates heat on the surface of the thermal head 3a in accordance with the image signal.
Line-type heating resistor rows 20 for each size 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 due to back tension during conveyance. It is configured. The image signal is generated from a control unit of a facsimile, an image scanner, an electronic blackboard, or the like, depending on the purpose.

On the other hand, a transfer recording layer 1a facing the thermal head 3a
A light irradiation means is provided on the side. As a light irradiation means, the emission wavelength range is different from each other, and microcapsules (
Two types of fluorescent lamps 3C that can react to A) and (B) individually are provided. The two types of fluorescent lamps include, for example, FLIOA70, which has a peak wavelength of 300 to 360 nm and reacts with the microcapsules (A).
E31/33T15 (λp = 313nm: Toshiba)
, FLIO^70E35/33T15 (λp = 335
r+m: Toshiba), FLIO^70BL/33T+5
(λp=352nm: Toshiba) Also, microcapsules (
FLR16R70-BA-37/33T1 as a fluorescent lamp with a peak wavelength of 360 to 430 nm that reacts with B)
6 (λP = 370nm: Matsushita), FLIO^7
One type of fluorescent lamp may be selected from among 0E39/33T15 (λp = 390 nm: Toshiba), etc., in correspondence with the absorption wavelength range of the photopolymerization initiator.

〔Example〕 The present invention will be explained in more detail with reference to Examples below.

Example 1 20 g of each of the components shown in Table 1 were microencapsulated by the method shown below.

Method for manufacturing microcapsules: Mix 100 g of water and 26 g of isobutylene-maleic anhydride copolymer (20.6%) (manufactured by Kureha Chemical Co., Ltd.),
3.1 g of pectin was added thereto and stirred for 20 minutes.

Then adjust p)l to 4.0 with 20% sulfuric acid solution,
0.2 g of Quadrol (BASF) was added. While stirring this at 3000 rpm with a homomixer, a solution prepared by dissolving 20 g of the components shown in Table 1 in 30 g of chloroform was added over 10 to 15 seconds, and emulsification was continued for 110 minutes.

The emulsion was transferred to a beaker of 500 mj2 and stirred with a stirring blade for 1 to 2 hours, and then the solvent was distilled off.

Table 1 Table 2 Next, 5g of urea, 12.0g of formalin (374k
) was added, the pH was adjusted to 5.0 with IN HCl,
The mixture was stirred as it was for 12 hours. After adjusting the pH to 2.0 with 1fi3N cI and stirring at 50°C for 3 hours,
After returning the solution to neutrality, the reaction solution was
It was poured into mA water and filtered. Next, add 1 of the above capsules.
Microcapsules (A) were produced by washing twice with 0,001 ml of water and drying.

On the other hand, microcapsules (B) were prepared by granulating and microcapsulating the ingredients shown in Table 2 in the same manner. At this time, the amount of wall material to be charged was 4.5 g of urea, 2 g of dihydroxynaphthalene, and formalin (37%) 12.
It was set to 0g.

PET (polyethylene terephthalate) film (
A thermoplastic polyester (Nippon Gosei Kagaku Kogyo Polyester-011) was diluted with toluene and applied to a thickness of 0.5 μm using an applicator. Next, the microcapsules (A) were spread on the film and unbound particles were shaken off. The thickness of the film is 10
Sandwiched between 0μm and 50μm PET films and heated to 110℃.
After passing through a beat roller at a temperature of 2 to 3 kg/c and a pressure of 1112 °C, the PET film was peeled off, and the microcapsules (A) were firmly attached to the PET film to produce a transfer recording medium. Similarly, a transfer recording medium was prepared in which microcapsules (B) and microcapsules (A) and (B) were mixed in equal amounts.

First, a transfer recording medium made of microcapsules (A) was wound into a roll and incorporated into the apparatus shown in FIG. The thermal head has a width of 2vn and 8 dots/m1.
An Il 8-4 size line type device was used in which the heating elements were arranged in rows or at the edges. As a fluorescent lamp, FLIOA70E35/33T15 (λp = 335
nm ) and FL10A70E39/33TI5 (λp
=390r+m) was used.

Next, as shown in the timing chart of FIG. 3, the lamp and thermal head were energized. In addition, the voltage and drive signal were controlled so that the temperature of the microcapsule (A) was approximately 100° C. for energizing the thermal head. By varying the energization time τ, we determined the time when the microcapsules (A) at the location where the signal was applied stopped being transferred at all.
Its pulse width (defined as sensitivity) fly p = 335 nm
It was 25 m5 for the light of λp = 3900a+, and 130 m5 for the light of λp = 3900a+. Similarly, when the sensitivity of the recording medium made of microcapsules (B) was determined, λ
20m5 for light with p=390nm. λp=33
It was +00m5 for 50m light.

Next, when the recording medium consisting of microcapsules (A) and (B) was energized at the timing shown in Figure 4, a good two-color image consisting of magenta and cyan could be formed without fogging or white spots. .

Example 2 The components shown in Table 3.4 were microencapsulated in the same manner as in Example 1, and the sensitivity was determined as a recording medium in the same manner as in Example 1. In addition, as a fluorescent lamp, FL10A70E31/3
3T15 (λp = 3+3 nm) and FLRI 6
R70-BA-37/33T16 (λp = 37O
r+m) was used.

Here, the shell material for encapsulating the ingredients in Table 3 is 4.5 g of melamine and 12 g of formalin, and the ingredients in Table 4 are 3.0 g of melamine and 2 g of dihydroxynaphthalene.
g, formalin 12 g.

Microcapsules consisting of the components in Table 3 are λp=313n
The sensitivity to w is 35m5, the sensitivity to λp = 370nm is 130m5, and the sensitivity to microcapsule fly p = 370rv consisting of Table 4 components is 3
5m5, sensitivity to λp = 313nm is 100m5
Met.

Next, when electricity was applied to the recording medium consisting of two types of microcapsules at the timing shown in Fig. 5, a good result was obtained.
A color image could be formed.

Table 3 Table 4 Comparative Example 1 The components shown in Table 2 were granulated and encapsulated in the same manner as in Example 1, and then supported on a support to produce a recording medium. In this case, 5 g of urea and 12.0 g (37 wt%) of formalin were used as wall materials for the capsule, and hydroxynaphthalene was not added.

Similarly to Example 1, λp = 335 nm, λp
When we measured the sensitivity to =390nm, we found that λp=3
2oI for 90nm light! The sensitivity was 1s, but the sensitivity was 70ms for light with λp = 335r+m, resulting in a decrease in wavelength selectivity.

Next, when the transfer recording medium mixed with the microcapsules (A) prepared in Example 1 was energized at the timing shown in FIG. 4, white spots were present.

〔Effect of the invention〕

As explained above, according to the present invention, a transfer recording medium comprising, as a recording layer, at least two types of microcapsules having wall materials of microcapsules having different absorption characteristics with respect to ultraviolet light provides high sensitivity and fogging. In addition, it is possible to form a multicolor image with less white spots and good wavelength selectivity.

In particular, in microcapsules where the main constituents of the wall material are urea-formalin or melamine-formalin resin and the absorption wavelength range is adjusted, the above effects are remarkable by introducing an aromatic ring having a hydroxyl group into the resin. As a result, the stability is further improved, and furthermore, the introduction of an aromatic ring having a hydroxyl group is easy, and the transfer recording medium of the present invention is extremely useful in practice.

[Brief explanation of the drawing]

FIG. 1(a) shows the results obtained using the transfer recording medium of the present invention. Explanatory diagram of the recording method performed in the order of (b) and (C), 2nd
The figure is a schematic diagram showing the configuration of a recording apparatus using the transfer recording medium of the present invention, and FIGS. 3, 4, and 5 are timing charts for applying heat and light in Examples. 1... Transfer recording body, la-image forming element, 1b.
...Base material, 2... Supply roll, 2 a---
Supply roll shaft, 3a-” recording head, 3c...
Light source, 4a... Transfer roller, 4b... Pressure roller, 5... Peeling roller, 6... Winding roll,
7...Cassette, 12a, 12b, 12cm--guide roller, 20...Thermal head, 20a-d...Heating resistor, M...Device main body.

Claims (1)

[Claims] 1. The recording layer on the support is composed of a plurality of types of microcapsules whose transfer characteristics change upon application of heat and light energy, and the plurality of types of microcapsules are ethylenically unsaturated double 1. A transfer recording medium comprising a compound having a bond, an internal phase comprising at least a different photopolymerization initiator and a colorant, and wall materials having different ultraviolet absorption characteristics. 2. The transfer record according to claim 1, wherein the main constituent component of the wall material is urea-formalin or melamine-formalin resin, and at least one type of microcapsule wall material contains an aromatic ring having a hydroxyl group. Medium.