JPS63139341A - Recording medium - Google Patents

Abstract

PURPOSE:To obtain the titled medium having high sensitivity and preservative stability and excellent light fastness and capable of giving a clear and high gradient image by incorporating a coloring agent and a sensitive component of a specific composition which sensitizes by light energy and heat or energy capable of converting to heat, to a transfer recording layer. CONSTITUTION:The transfer recording layer contains the coloring agent and the sensitive component which sensitizes by the light energy and the heat or the energy capable of converting to the heat. The sensitive component contains at least the photopolymerization initiator and a monomer having an unsatd. double bond or its oligomer or its polymer or a mixture thereof. The photopolymerization initiator is composed of at least one kind of the compd. selected from thioxanthone derivatives and amines. The transfer recording layer is formed by sticking the powdery image forming material which has the prescribed composition and contains a binding agent on a substrate body. The image forming material is used in a form of a capsule which is coated with a wall material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel recording medium used in recording devices such as printers, copying machines, and facsimiles. In particular, the present invention relates to a recording medium used in a recording method suitable for one-shot color recording.

[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. One such recording method is the thermal transfer recording method, which uses equipment that is lightweight, compact, and noiseless.
It has excellent operability and maintainability, and has been widely used recently. According to this method, plain paper can be used as the transfer medium.

[Problem that the invention seeks to solve]

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 degrees of unevenness due to entangled fibers. Therefore, according to the conventional thermal transfer recording method, the edges of the printed image may not be sharp or a portion of the image may be missing, resulting in a reduction in print quality.

Furthermore, in conventional thermal transfer recording methods, the ink layer is transferred to the transfer medium using only heat from the thermal head, or the thermal head must be cooled to a predetermined temperature within a limited short period of time. Furthermore, it is logically difficult to increase the amount of heat co-supplied from the thermal head because thermal crosstalk between the heat generating segments that make up the thermal head surface must be prevented. Therefore,
High-speed recording is difficult with conventional thermal transfer recording methods.

In addition, because thermal conduction has a slower response than electricity or light, it is generally difficult to control heat pulses to the extent that halftones can be reproduced when recording with conventional thermal heads. Since the thermal transfer ink layer does not have a gradation transfer function, halftone recording is not possible.

In addition, with conventional thermal transfer recording methods, only one color image can be obtained with one transfer, so to obtain a multicolor image, the colors must be overlapped by repeating the transfer multiple times. was necessary. 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, it has been difficult to obtain clear multicolor images 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.

Further, US Pat. No. 4,399,209 discloses a system that uses a color former and a color developer to form a multicolor visible image. U.S. Pat. No. 4,399,209 uses a recording medium in which microcapsules containing a photosensitive composition and a coloring agent are arranged on a substrate, and uses mainly ultraviolet light converted in accordance with a recorded image to The photosensitive composition inside the capsule is cured to form a transferred image, and this transferred image is then applied to a recording medium having a color developing layer and passed through a nip between a pair of pressure rollers to destroy the microcapsules. Furthermore, a transfer image forming system for developing an image is disclosed. A multicolor image is obtained by image-formingly transferring a color former to an image forming sheet, where the color former reacts to form an image.

Further, US Pat. No. 4,416,966 discloses a self-contained color developer in which the color developer is present on the same support surface as the photosensitive microcapsules.
) discloses an image forming system. After exposure, primarily by ultraviolet light converted in accordance with the recorded image, the microcapsules rupture and release the internal phase imagewise when the imaging sheet is passed through a pressure roll. The color former then migrates to a developer, usually provided in a separate layer, where it reacts and forms a color image.

Both of the recording methods such as method 2 contain a photopolymerization initiator in a microcapsule, and the photopolymerization initiator has different photosensitive wavelength ranges, and is converted to correspond to each photosensitive wavelength range. The contents inside the microcapsules are cured mainly by ultraviolet light. However, the common problem with these methods is that the means used for image formation mainly irradiates only ultraviolet light, that is, optical energy, onto the substrate on which the microcapsules are arranged, which makes it difficult to form a transferred latent image on the recording medium. To form a clear recorded image at high speed, it was necessary to use a photosensitive material that is highly sensitive to light or to irradiate it with high energy light.

However, high-sensitivity recording media that utilize only photoreactions have the fatal drawback of high sensitivity when irradiated with light and poor storage stability near room temperature. Furthermore, in order to obtain high-energy light, the apparatus becomes large, and in order to obtain multicolor recording, the apparatus becomes large and the apparatus cost becomes large, which is not desirable in practice. In addition, since the above method uses only light energy to form an image, it
When outputting an image in response to an external signal, or when converting an image read from a color document into a digital signal using a color image scanner, such as in a color copying machine, and then adding image information to a recording medium, It's inappropriate. That is, when irradiating high-energy light, it is necessary to use short wavelength light, mainly ultraviolet light, and a digitally controllable light source for ultraviolet light is currently not available. For example, as a method for obtaining a digital light source, optical heads such as liquid crystal shutter arrays and LED arrays have been devised, but although these are suitable for miniaturization, liquid crystal molecules deteriorate at wavelengths in the ultraviolet region. UV light cannot be extracted.

Furthermore, since the color development method uses leuco dye, it has the drawback that the stability of recorded images is essentially poor.

Furthermore, in order to facilitate development by applying pressure after exposure, the contents of the microcapsules need to be a photosensitive composition that has a liquid phase at room temperature, resulting in poor storage stability and the resulting images remain unrefined. Due to the destruction of the reactants, there is an odor from the monomers present, which is a property that is not desirable in practice.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional problems, and provides an image forming method that solves such problems, that is, can form a high-quality transferred image, can perform high-speed recording, and can perform halftone recording. The main object of the present invention is to provide a recording medium that can be effectively used in an image forming method that allows for.

A further object of the present invention is to provide a recording medium that does not require a special color developing layer and can form a clear transferred image on commonly used plain paper with low surface smoothness.

A further object of the present invention is to provide a highly sensitive recording medium that can record digital images with low power without requiring a special digital light source with high optical energy.

Furthermore, an object of the present invention is to provide a recording medium with high storage stability and high sensitivity.

A further object of the present invention is to provide a recording medium on which recorded images with excellent light resistance can be obtained.

A further object of the present invention is to provide a recording medium that can produce clear, multicolor recorded images with high gradation using a small and inexpensive device.

A further object of the present invention is to provide a recording medium that can be used in an image forming method with extremely little environmental dependence during latent image formation.

[Means for solving problems]

The above-mentioned object of the present invention is to provide a transfer recording layer in which the physical properties governing the transfer characteristics of the transfer recording layer change by simultaneously applying a plurality of types of energy including light and at least one type of energy corresponding to image recording information. on a support, the transfer recording layer comprising at least a colorant and a sensitive component that is sensitive to the application of light energy and heat or heat convertible energy, and is a solid image at room temperature. the sensitive component contains at least a photopolymerization initiator and a monomer, oligomer, polymer or mixture thereof having an unsaturated double bond, and the photopolymerization initiator is selected from thioxanthone derivatives. This is achieved by a recording medium comprising at least one type of compound and amines.

To perform transfer recording using the recording medium of the present invention, first, multiple types of energy including light are simultaneously applied to the transfer layer in correspondence with the image recording information, thereby improving the transfer characteristics. The physical properties that govern the transfer are changed, and the transferred image formed by the portion where the physical properties have changed is transferred to the transfer recording medium by using, for example, heating and pressure. The physical properties that govern this transfer characteristic are arbitrarily determined depending on the type of recording medium used. For example, in the case of a transfer recording medium that transfers the transferred image in a thermally molten state, it is determined by the melting temperature, softening temperature, or , the glass transition point, etc., and in the case of a transfer recording medium in which the transferred image is transferred to the transfer medium in an adhesive state or in a permeable state, it is the viscosity at the same temperature. Further, the plurality of types of energy used to form the transferred image are arbitrarily determined depending on the type of recording medium used, and for example, a photoelectron beam, heat, pressure, etc. are used in an appropriate combination.

A preferred image forming method for forming an image on the recording medium of the present invention will be described. In order to understand this, an example using a recording medium on which a transferred image is formed by light and thermal energy will be explained with reference to FIGS. 1a to 1d.

The time axes (horizontal axes) of the graphs in FIGS. 1a to 1d correspond to each other. Further, the transfer recording layer contains at least a photopolymerization initiator and a monomer, oligomer, or polymer having an unsaturated double bond, which will be described later, as a sensitive component. FIG. 1a shows the rise in the surface temperature of the heating means and the subsequent temperature drop when the heating means such as a thermal head is driven under the development heat from time 0 to 73. The transfer recording medium that is in pressure contact with the heating means exhibits a temperature change as shown in FIG. 1b as the temperature of the heating means changes. That is, the temperature rises with a time delay of tl, reaches the maximum temperature at time t4, which is also delayed from t3, and then decreases thereafter.

Let Ts be the softening temperature of the transfer recording layer. The viscosity of the transfer recording layer decreases rapidly in a temperature range of Ts or higher. This situation is shown by curve A in FIG. 1C. After reaching Ts at time t2, the viscosity continues to decrease until time t4, when the maximum temperature is reached, and as the temperature decreases, the viscosity increases again and shows a rapid increase until time 6, when it drops to Ts. In this case, the physical properties of the transfer recording layer are basically unchanged from those before heating, and when heated to a temperature Ts or higher in the next transfer step, the viscosity decreases in the same manner as described above.

Therefore, if the transfer recording layer is brought into pressure contact with the transfer medium and heated to a temperature necessary for transfer, for example, above Ts, the transfer recording layer will be transferred for the same reason as the transfer mechanism of conventional thermal transfer recording. In this case, as shown in Fig. 1d, if the transfer recording layer is heated and light irradiated at the same time as time t2, the transfer recording layer is softened and, for example, a reaction initiator contained in the transfer recording layer is activated, and the temperature or reaction rate is increased. If the temperature is increased enough to increase the temperature, the probability that the polymerizable monomer will polymerize increases dramatically, so that curing progresses rapidly.

When heating and light irradiation are performed simultaneously in this manner, the transfer recording layer exhibits a behavior as shown by curve B in FIG. 1C. As the reaction progresses, the softening temperature rises and changes from Ts to T's at time t5 when crosslinking ends. This situation is shown in FIG. 1d. Therefore, when heated in the next transfer process, Ts'
There is a difference in properties between the part that has changed and the part that has not changed. Along with this, the transfer start temperature Ta, which is the temperature at which the transfer recording layer starts transferring, also changes and becomes Ta'.

Therefore, by heating to Tr that satisfies, for example, Ta<Tr<Ta', only the portion where the softening temperature does not rise will be transferred to the transfer medium. Although it depends on the temperature stability accuracy of the transfer process, Ts' - Ts at this time is preferably about 20°C or more. In particular, 40
℃ or higher is preferable. This value is also the same when Ts>Ts'. In this way, a transfer image can be formed by controlling heating or non-heating according to the image signal and simultaneously irradiating light.

In addition to the softening temperature explained above, the physical properties that govern the transfer characteristics of the transfer recording layer include the melting temperature and the glass transition point, but in any case, the melting temperature before and after the application of multiple types of energy , a transfer image is formed in the transfer recording layer by utilizing irreversible changes such as the glass transition point. Further, the softening temperature, melting temperature, and glass transition point vary in almost the same manner, so the above explanation using the softening temperature is also an explanation using the melting temperature and the glass transition point.

Incidentally, the transfer start temperature in the present invention is measured in a linear manner.

A 6 μ thick transfer recording layer coated on a polyethylene terephthalate (PET) film and a surface smoothness (Beck smoothness) used as a transfer medium of 50 to 200 seconds and a thickness of 0.
．． The transfer recording medium and the high-quality paper are sandwiched between the following two rolls, with the 2mm high-quality paper facing each other, and the transfer rate is 2.5 mm/sec.
It is transported at a speed of c. The first roll of the two rolls is placed on the side of the transfer recording medium and is an iron roll with a built-in 300W halogen heater, and has a diameter of 401001 mm. In addition, the second roll on the high-quality paper side is an iron roll with a diameter of 40 LI 1 m, the surface of which is coated with 0.5 mm thick fluororubber, and the two rolls face each other with a linear pressure of 4 kg/cm. There is. The surface of the first roll is detected by a thermistor, and the halogen heater is controlled to maintain it at a predetermined temperature. Four seconds after passing between the two rolls, while keeping the high-quality paper flat, the transfer recording medium was pulled at an angle of approximately 90° at a speed equal to the transport speed of the rolls, and the high-quality paper was separated from the transfer recording medium. , Observe whether or not the transfer recording layer has been transferred to the high-quality paper. In this way, while gradually increasing the surface temperature of the heat roll (first roll) (heating rate: 10°C/M I N
(Below) Measure the temperature when the optical density of the transferred image is saturated and find out the transfer start temperature.

Here, physical property changes governing transfer include changes in the glass transition temperature Tg or softening temperature Ts of the recording medium;
However, since the recording medium of the present invention obtains a recorded image in the subsequent transfer step, it is sufficient that the adhesion state or permeability state to the recording medium changes, and the clear above-mentioned Tg.

Adaptation is possible even without a change in Ts or Tm.

In addition, the multiple types of energy used only to form a transferred image include light and heat, or electricity that can be converted into heat;
A combination of energy selected from ultrasonic waves and pressure is preferable in terms of energy efficiency.

Next, the photopolymerization initiator, which is a component of the recording medium of the present invention, will be explained. It is well known that in the presence of amines, thioxanthone derivatives abstract hydrogen from the amines when irradiated with light and efficiently generate reactive species.

Furthermore, in the present invention, recording is performed by applying light energy and heat or energy that can be converted into heat to the reactive component of the recording medium, but since the sensitive component of the recording medium is solid at room temperature, heat or heat that can be converted to heat is The application of energy greatly changes the diffusion rate of the photopolymerization initiator contained in the sensitive component, thereby increasing the reaction rate.

When the photopolymerization initiator is a composite photopolymerization initiator consisting of a thioxanthone derivative and an amine, and reactive species are generated only when the two are associated, the above-mentioned influence on the diffusion rate becomes even greater.

In other words, when only light energy is applied, the diffusion rate of thioxanthone derivatives and amines is low in the solid sensitive component, and therefore the reaction hardly progresses, but when light energy and heat or energy that can be converted to heat is applied , the rate of diffusion of both companies increases, and the probability of meeting becomes very large, so the reaction progresses rapidly. As described above, by using a photopolymerization initiator consisting of a thioxanthone derivative and an amine in the recording medium of the present invention, a recording medium with good recording contrast and high sensitivity can be obtained.

The thioxanthone derivatives used in the present invention include thioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 2.5-ditylthioxanthone, 2. -5-diisopropylthioxanthone, 2-methylthioxanthone or Ciba-Geigy Co., Ltd. (Publication Patent Publication No. 154970/1970), which is described in the following formula (I) [wherein X is hydrogen, halogen, -CN, -OH, −
5H, -NH2, -No2. -5o3H, phenylsulfonyl, or alkylsulfonyl, alkyl, alkoxy, alkylthio, alkylamino, dialkylamino, or -CO-alkyl groups each having 1 to 4 carbon atoms in each alkyl moiety, or further -C
OOR+, -Co SR+, Co N (R
+ ) (R2) represents a CO-piperidyl, -co-pyrrolidinyl, or -〇〇-morpholinyl group, and Z is hydrogen, halogen, -OH, -SH, or each alkyl moiety has 1 to 4 carbon atoms means an alkyl, alkoxy, alkylthi, or dialkylamino group having an atom, and Y is -OR,-.

S R+ , N (R+ ) (R2) represents a piperidyl, pyrrolidinyl, or soriphorine group, and R
1 is an alkyl group having 1 to 24 carbon atoms, 3
alkoxyalkyl having from 1 to 10 carbon atoms, C3 to c8 cycloalkyl, phenyl, naphthyl, -(CH2)mphenyl or -(CH2C
H20)n CH3 group, R2 means hydrogen or one residue of R, m is a number of 1 or 2, and n is 2 to 1
is an integer of 0, in which case at least one of X and Z is
The -co-Y group is at the 4-position, and the group Y is at the 0c
When H3 is meant, it is not hydrogen. ], but the present invention is not limited thereto.

The aromatic amines used in combination include ethyl-P-dimethylaminobenzoate and methyl-P-dimethylaminobenzoate.
Dimethylaminobenzoate, isoamyl-P-dimethylaminobenzoate, phenyl-P-dimethylaminobenzoate, ethyl-P-diethylaminobenzoate, phenyl-P-diethylaminobenzoate, N,
N-dimethylaniline, N, N-diethylaniline, N
, N-dimethylbenzylamine, N-benzyl-N-mitylaniline, N,N-dibenzylaniline, triphenylamine, etc. Aliphatic amines include trimethylamine, triethylamine, tripropylamine, dimethylcyclohexylamine, triethanolamine, etc. Examples of the polyamine include methylene diamine, hexamethylene amine, 1,4-cyclohexane diamine, and phenylene diamine, but the present invention is not limited thereto.

The above-mentioned amines may be used in combination of two or more.

The amount of photopolymerization initiator (thioxanthone derivative + amines) contained in the sensitive component of the present invention is preferably about 1:
The ratio can range from 5 to about 1:1000, more preferably from about 1:10 to about 1:100.

The weight ratio of the components of the photoinitiator to thioxanthone derivative to amines is preferably from about 30:1 to about 1:30, more preferably from about 1O:1 to about 1:10.

In addition, monomers, oligomers, and polymers having unsaturated double bonds used in the present invention include polyisocyanates (which may be reacted with polyols if necessary), alcohols, and amines having unsaturated double bonds. Urethane acrylates and urethane methacrylates having urethane bonds synthesized by polyaddition reactions of epoxy resins, and epoxy acrylates, polyester acrylates, and spin acrylates synthesized by addition reactions of epoxy resins with acrylic acid or methacrylic acid. , polyether acrylates, etc., but the present invention is not limited thereto.

In addition, as a polymer, it has tubes such as polyalkyl, polyether, polyester, polyurethane in the main chain,
Examples include those in which a polymerizable or crosslinkable reactive group such as an acrylic group, a methacrylic group, a cinnamoyl group, a cinnamylidene acetyl group, a furyl acryloyl group, or a cinnamic acid ester is introduced into the side chain. It is not limited to this.

Furthermore, 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, they can be maintained in a semi-solid or solid state by mixing with the binder described below. It doesn't matter.

Any organic polymer may be used as the binder as long as it is compatible with the monomer, oligomer, or polymer having unsaturated double bonds.

As the binder, a conventionally known organic polymer is used. Examples include addition polymers having carboxyl groups in side chains, such as methacrylic acid copolymers, acrylic acid copolymers, itaconic acid copolymers, partially esterified maleic acid copolymers, and maleic acid copolymers. In addition, chlorinated polyethylene, chlorinated polypropylene, and chlorinated polyolefin.

Copolymers of polymethyl methacrylate, polyacrylic acid, polymethacrylic acid, polyacrylic acid, alkyl esters, acrylic acid alkyl esters and acrylonitrile, vinyl chloride, vinylidene chloride, styrene, butadiene, polyvinyl chloride, vinyl chloride and Acrylonitrile copolymer.

Polyvinylidene chloride, copolymer of vinylidene chloride and acrylonitrile, polyvinyl acetate, copolymer of vinyl acetate and vinyl chloride, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylonitrile, copolymer of acrylonitrile and styrene, acrylonitrile and butadiene and copolymers with styrene, polyvinyl alkyl ether,
Polymethyl vinyl ketone, polyethyl vinyl ketone, polyethylene, polypropylene, polystyrene, polyamide, polybutadiene, polyisoprene, polyurethane,
Examples include polyethylene terephthalate, chlorinated rubber, polychloroprene, polystyrene-butadiene copolymer, and the like. Among the above polymers, polyethylene chloride, polymethyl methacrylate, polyvinyl chloride, vinylidene chloride-acrylonitrile copolymer,
Examples include polystyrene, styrene-acrylic copolymer, polyvinyl butyral, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, and chlorinated rubber. These may be used alone or in a mixture of two or more. The binder is 1wt% to 90wt%, preferably 1wt% based on the sensitive component.
The content is from wt% to 60wt%.

Waxes, whether compatible or incompatible, are also used, including vegetable waxes such as candelilla wax, carnauba wax, and rice wax, animal waxes such as beeswax and spermaceti, and ceresin and montan waxes. There are mineral waxes, petroleum waxes such as paraffin wax, polyethylene wax, Sasol wax, montan wax derivatives, paraffin wax derivatives, hydrogenated castor oil, hydrogenated castor oil derivatives, and synthetic waxes made of fatty acids and fatty acid amide esters such as stearic acid. In the present invention, one type or a mixture of two or more types of these waxes may be used.

The colorant is a component contained in order to form a chemically 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 Red Red, Hansa Yellow, Benjishi Yellow, Brilliant Carmine 6B, Lake Red C, Permanent Red F5R, Phthalocyanine Blue, and Victoria Blue. Organic pigments such as Lake, Fast Sky Blue, and colorants such as leuco dyes and phthalocyanine dyes can be used.

The amount of the colorant is preferably 0.1 to 30 parts by weight based on the sensitive component and the binding composition. Furthermore, additives such as thermal polymerization inhibitors and plasticizers may be added to the sensitive component of the present invention, if necessary.

Even if the above-mentioned sensitive component is dissolved in a solvent and coated on a support in a continuous layer, the sensitive component can be formed into a particulate image-forming element, or the particulate image-forming element can be microencapsulated. It may be applied onto a support. The support used in the present invention is selected from film-like materials such as polyethylene terephthalate and polyamide.

The support may be provided with other coating layers, an antihalation layer, an ultraviolet absorbing layer, or a visible light absorbing layer on its surface, if necessary, to facilitate bonding.

Furthermore, in order to prevent a decrease in sensitivity due to oxygen, the composition of the present invention is provided with a removable transparent cover, or a transparent cover is provided on the photosensitive layer as described in Japanese Patent Publication No. 40-17828. A coating layer with low oxygen permeability can be provided.

Furthermore, in the present invention, multicolor image formation is possible by using conventionally known photopolymerization initiators having different photosensitive wavelength ranges.

The recording medium based on the present invention can be used by coating a single layer on a base film, but in order to prevent a decrease in sensitivity due to oxygen inhibition in the atmosphere, a film of polyethylene, polypropylene, etc. can be coated on the recording medium. It is also effective to apply pressure to the transfer recorder and peel it off after the transfer image is formed. Furthermore, if the image-forming element is granulated and coated with a high molecular compound having low oxygen permeability, the layer for preventing a decrease in sensitivity can also improve image resolution. Furthermore, we microcapsulated multiple types of compositions consisting of coloring materials and photopolymerization initiators with different photosensitive wavelength ranges, and randomly supported them on the base film to create microcapsules that correspond to the photopolymerization wavelength ranges of each photopolymerization initiator. By simultaneously applying a plurality of types of energy including light of different wavelengths, at least one type of energy corresponding to image recording information, a recording medium compatible with color recording can be obtained.

When microcapsules are used in the image forming element constituting the transfer recording layer, the above-described material is contained in the core portion. Materials used for the wall material of microcapsules include, for example, gelatin, gelatin-gum arabic, sodium alginate, polyvinyl alcohol, ethyl cellulose, nitrocellulose, cellulose-based urea-formalin such as nitrocellulose, resorcinol-formaldehyde, urea-formaldehyde, incyanate. , incyanate-polyol, melamine-formaldehyde,
Hydroxypropyl cellulose, polyvinyl chloride, polyvinyl chloride-cellulose, acetate butyrate, polyvinyl acetate, polystyrene, polyethylene, polymethyl methacrylate, polyamide, styrene-acrylonitrile copolymer, vinylisodene chloride-acrylonitrile copolymer, epoxy Resin, polyvinyl formal, vinyl chloride-vinyl acetate copolymer, polyester, polyacrylate, cellulose acetate butyrate, polyvinyl pyrodone, polyvinylidene chloride, nylon, tetron, urethane, polycarbonate, maleic anhydride copolymer , polyethylene terephthalate, etc. are used.

In the transfer recording medium of the present invention, the thickness of the transfer recording layer is 1 to 20
μ is preferable, and 3 to 10 μ is particularly preferable. When the transfer recording layer is composed of image forming elements of microcapsules, the particle size of the macrocapsules 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 2.0μ,
Particularly preferred is 0.1 to 0.5μ.

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

The microcapsule image forming element is bound to the substrate using a coating binder such as polyvinyl alcohol (PVA) or epoxy adhesive. The thickness of the coating binder is preferably 0.1 to 1 μm.

In the recording medium of the present invention, radical reactions in the transfer recording layer may be suppressed due to oxygen in the air. In order to prevent this, it is preferable to apply, for example, an aqueous polyvinyl alcohol solution to which a small amount of a surfactant is added as an oxygen-preventing layer on the transfer recording layer. This oxygen prevention layer is removed by washing with water after the transfer image is formed. In addition, in the case of a microencapsulated element, the wall material can have a function as an oxygen prevention layer.

The recording medium of the present invention can be manufactured, for example, as follows.

The recording medium of the present invention is prepared by melt-mixing components such as a sensitive component, a stabilizer, a coloring agent, and applying the mixture onto a substrate using an applicator or the like. In addition, when the transfer recording layer is constituted by an image forming element, the above-mentioned components are made into minute image forming elements by spray drying method etc. for each color, and then each color image forming element is formed with a binder such as a polyester resin. After sufficiently mixing the body in a solvent such as methyl ethyl ketone or ethylene glycol diacetate, solvent vent coating is performed on a film such as polyimide, and the desired recording medium is prepared by drying at 80°C for 3 minutes to remove the solvent. You can get it.

When the image forming element is composed of microcapsules, for example, the image forming element of microcapsules is manufactured by the method detailed in the Examples below,
It is coated on a substrate by a solvent coating method in the same manner as in the case of image forming elements on particles.

Further, the particulate element may be electrostatically attached to a support, and in that case, the particulate element, the support, or both may be corona-charged. J Charging and adhesion.

The method of physically or chemically supporting the image forming element on the support as referred to in the present invention-1 "" includes the above-mentioned solvent coating method and electrostatic adhesion method. Examples of chemical methods include a method in which a functional group is provided on each surface of the contacting surface of the image forming element and the support to chemically bond the image forming element and the support.

Examples of the support include polyester, polycarbonate, triacetylcellulose, nylon, polyimide, polyethylene terephthalate, and metals such as aluminum, and these may be in the form of a film, plate, drum, or sphere.

〔Example〕

The present invention will be explained below using examples.

Examples 1 to 9 The components shown in Table 1 were dissolved in dichloromethane solvent,
It was coated at a thickness of 4-4 on polyethylene terephthalate with a thickness of 6 microns. Polyvinyl alcohol (Mll) is applied on this membrane.
-1200) Oxygen prevention film coated with aqueous solution (film thickness 1O-)
was formed and used as a sample. Next, the sample prepared by the above method was wound into a roll and incorporated into the apparatus shown in FIG. 2.

The thermal bed 4 is an A-4 size line type with 8 dots/mm and heat generating element arrays are arranged at the edges, and the heat generating elements are pressed against the heat generating elements by the tension of the transfer recording medium 1 = 3 lines. I made it look like this. Then, chemical lamps 3 were placed at opposing locations.

Next, the heat generation of the thermal head is controlled according to the image signal.

In this embodiment, since the transfer recording layer is treated with light and heat applied to raise the glass transition point and the transfer start temperature, negative recording is performed. That is, the control of the thermal head is such that it does not conduct electricity when a mark signal (black) is received, but it energizes and generates heat when it is not a mark signal (white). The energizing energy when this heat is generated is 0.8w/dotx x m5ec, and the chemical lamp is used to synchronize with the signal of the thermal head to
Control and drive the thermal head according to the image signal in the manner described above while uniformizing c-light irradiation.2 x m5ec
The transfer recording medium was synchronously conveyed by a stepping motor and a drive rubber roll at a repeating cycle of /line.

Next, the polyvinyl alcohol film was removed, and as shown in FIG.
It was transported by sandwiching it between the two. The heat roll 8 had a 300 W heater inside, and the heater was controlled to maintain the surface at an arbitrary temperature in the range of 50 to 150° C. using an aluminum roll whose surface was coated with 2 mm thick silicone rubber. Pinch Roll 9 is JI
The pressure was set at 1 to 1.5 Kg/c+n3 using a silicone rubber roll with a hardness of 50° measured by an S rubber hardness meter. Beat roll, 1
After conveying plain paper over the transfer recording layer in a temperature range of 10° C. to 130° C., the substrate film was peeled off and the minimum time X m5ec during which an image was obtained was determined and the sensitivity was determined. (However, X is 2
m5ec, 5 m5ec, romsec, hereafter 5 m
In other words, the smaller the value of X, the higher the sensitivity. Moreover, the obtained image was a high-quality image with good fixability.

Next, Table 2 shows the sensitivity X m5ec of combinations of amines and thioxanthone derivatives.

The chemical lamp shown in Figure 2 and 3 is FL1 manufactured by Jikken.
0A70E39 (emission peak 390 nm) was used.

As understood from Table 2, it can be seen that a highly sensitive recording medium can be obtained by using a thioxanthone derivative and an amine in combination as a photoinitiator.

Next, an example of creating a multicolor image using the recording medium of the present invention will be shown.

Example 10) Here, a multicolor image was created using 4,4'-dichlorobenzophenone, which has a photosensitive wavelength range different from that of the thioxanthone derivative, as a photopolymerization initiator.

As shown in FIG. 4, the transfer recording layer 1b is formed by forming a microcapsule-shaped image forming element by the following method using materials having the compositions shown in Tables 3, 4, and 4 as the core IC%ld. .

First, the log of the ingredients shown in Tables 3 and 4 was mixed with 20 parts by weight of methylene chloride, and then a surfactant such as a cationic or nonionic surfactant with an HLB value of at least 10 or more and 1 g of gelatin were added. Add 200ml of dissolved water and heat at 60°C with a homomixer at 8,000-10,000 rpm.
Stir to emulsify and obtain oil droplets with an average particle size of 26p. Stirring is continued at 60°C for 30 minutes, and methylene chloride is distilled off to bring the average particle size to the top. Add 20xxl of water in which gum arabic Ig was dissolved, cool slowly, and then add N)140) + (ammonia) water.
A microcapsule slurry is obtained by increasing the temperature to h11 or more, and 1.0 ml of a 20% glutaraldehyde aqueous solution is slowly added to harden the capsule walls.

After that, solid-liquid separation was carried out using a Nutsche filter, and 35
C. for 10 hours to obtain a microcapsule-shaped image forming element.

This image forming element includes the core lc shown in Tables 3 and 4,
ld is a microcapsule coated with shell 1e, the particle size is 7 to 15p, and the average particle size is 10μ.

The image forming element formed as described above was coated with 5% PVA.
A transfer recording layer 1b is formed by adhering to a support made of a polyethylene terephthalate film having a thickness of 6p using an adhesive 1f made by dropping a few drops of a surfactant per 10cc of an aqueous solution, thereby forming a recording medium 1. .

The thioxanthone derivative in the image forming element shown in Table 3 absorbs light in the band of graph C in the light absorption characteristics shown in FIG. 5, and becomes magenta in color during image formation. 4,4'-dichlorobenzophenone absorbs light in the band of graph D in the absorption characteristics shown in FIG. 5, and becomes blue when forming an image. Next, the transfer recording layer 1b
was wound into a roll and assembled into the apparatus shown in FIG.

However, the light source indicated by 3 here is lamp E (manufactured by Jikken Co., Ltd. FL10A70E39) with a luminescence peak of 390 mm, corresponding to the thioxanthone derivative exhibiting the above-mentioned absorption characteristics.
Emission peak 3 corresponding to '-dichlorobenzophenone
] 33m lamp F (Mitsumi Co., Ltd. FL10A70E
31). The transfer recording layer 1b has the property that when light and heat of a predetermined wavelength are applied, the softening point temperature rises and the transfer recording layer 1b is no longer transferred to the recording paper. During color recording, power is not applied to the heating element corresponding to the magenta color of the image signal in the heating element row of the thermal head, but a current of 20+n5ec is applied to the portion corresponding to the white color of the image signal (the recording medium is assumed to be white), and at the same time the lamp is turned on. E is uniformly irradiated for an irradiation time of 25 m5 ec.

Next, when recording blue color, after 50 m5 ec has passed after the end of the irradiation, that is, 7511 Isec9 from the energization time.
This time, among the heating element rows of the thermal head, the heating element corresponding to the blue color of the image signal is not energized, but the part corresponding to the white color of the image signal is energized for 60m5ec, and at the same time, the lamp F is turned on for an irradiation time of 70m5ec. irradiate in a similar manner. In the manner described above, the thermal head is controlled according to the blue, magenta, and white image signals to form a negative image on the transfer recording layer 1b, and 1
The transfer recording medium 1 is conveyed synchronously at a repeating cycle of 50 m5ec/1ine.

Next, as in Example 1), plain paper was layered on the transfer recording layer,
By applying pressure and heating, a two-color transfer image of blue and magenta can be transferred onto plain paper.

As described above, two-color recording is performed in one shot.

〔Effect of the invention〕

As explained above, if the recording medium of the present invention is used, the formation of a latent image corresponding to an image and the transfer recording are performed in separate processes, so a high-quality image can be formed and halftone recording is possible. Furthermore, multicolor recorded images can be easily and inexpensively formed.Furthermore, when the transfer recording layer is composed of granular image forming elements, the individual solid image forming elements adhere to the recording material. Because transfer recording is performed, a clear, fog-free recorded image can be obtained even on commonly used plain paper with low surface smoothness.Furthermore, it uses light and heat, or energy that can be converted into heat, to form a latent image. Furthermore, the recording medium of the present invention is one in which a latent image is formed only when light and heat or energy that can be converted into heat is simultaneously applied. Therefore, it is possible to simultaneously satisfy both high-sensitivity recording and storage stability.

[Brief explanation of the drawing]

Figures 1a to 1d are diagrams of the principle of transfer recording using the recording medium of the present invention, and Figures 2 and 3 are schematic diagrams of an apparatus for performing transfer recording using the recording medium of the present invention. , FIG. 4 is a configuration diagram of the transfer recording medium, FIG. 5 is a graph showing the absorption characteristics of the core component, and FIG. 6 is a timing chart for applying heat and light. DESCRIPTION OF SYMBOLS 1... Recording medium, 1a... Support, 1b... Transfer recording layer, Ic, ld... Core, 1e... Shell (
wall material), 1f...adhesive, 2...supply roll, 3.
... Lamp, 4... Thermal head, 5... Control circuit, 7... Heater, 8... Heat roller, 9...
... Pinch roller - 1I O - ... Plain paper, 11 ...
Winding roll, 12...recorded image,

Claims (4)

[Claims] (1) By simultaneously applying multiple types of energy, including light, at least one type of energy corresponding to image recording information, a transfer recording layer whose physical properties governing its transfer characteristics change can be formed on a support. an image-forming element that is solid at room temperature, the transfer recording layer comprising at least a colorant and a sensitive component that is sensitive to the application of light energy and heat or heat-convertible energy; The sensitive component contains at least a photopolymerization initiator and a monomer, oligomer, polymer, or a mixture thereof having an unsaturated double bond, and the photopolymerization initiator is at least one selected from thioxanthone derivatives. A recording medium comprising a compound and an amine. (2) The recording medium according to claim 1, wherein the image forming element contains a binder. (3) Claim 1 or 2, wherein the image forming element is in the form of particles and is physically or chemically supported on the support to form a layer. recording medium. (4) The recording medium according to claim 3, wherein the image forming element is covered and encapsulated with a wall material.