JP2002144776A - Image forming body and card with image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming body and a card with an image with high resolution, rich expression of gradation by area gradation, excellent image durability, high optical density of the image and excellent image. SOLUTION: The card with the image characterized by providing the image formed with a plurality of colors of ink dots 31, 32 and 33 on a substrate 21 and a transparent layer 22 provided so as to cover the image and having a colored pigment, a non-crystalline organic polymer and a colorless or light- colored fine particle as main ingredients of the ink and having film thicknesses of the dots of 0.2-1.0 μm is provided and especially, it is preferable for the ink that at least 80 wt.% of the colored pigment are the organic pigment and the mean particle diameter is in a range of 50-500 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming body provided with a multicolor image based on an area gradation, such as a booklet-shaped passport (passport), a passbook, a visa (visa) or a card with an image (for example, , IC card, contactless card,
Hybrid cards, memory cards, rewritable cards, magnetic cards), and in particular, using a thermal transfer recording medium (thermal transfer ribbon) using a thermal transfer recording layer containing a color pigment and a thermal head printer, and performing thermal transfer based on image data The present invention relates to a card with an image on which an image having an area gradation by dots is formed by thermal transfer recording in which a recording layer (ink layer) is thermally transferred onto an image receiving sheet like an image.

[0002]

2. Description of the Related Art Conventionally, as a thermal transfer recording method for forming a gradation image using a thermal head printer, a sublimation transfer method using a sublimable dye and a traditional (a wax rich in ink) fusion transfer method are used. Widely known.

In the sublimation transfer system, a thermal transfer recording medium having a thermal transfer recording layer mainly composed of a sublimable dye (heat transfer dye) and a binder resin provided on a support is superimposed on an image receiving sheet and heated by a thermal head or the like. A gradation image is formed by heating the device according to image information and transferring the sublimable dye in the thermal transfer recording layer onto the image receiving sheet according to the amount of heat applied.

However, when an image is formed using such a sublimable dye (heat transfer dye), the formed image is inferior in durability, and its use in fields requiring heat resistance and light resistance is limited. Is done. In addition, the thermal recording sensitivity is lower than that of the melt transfer method, so the printer is driven by a battery such as a dry battery, making it smaller and lighter, and is not suitable as a high-speed recording material using a high-resolution thermal head expected to be used in the future. have.

[0005] On the other hand, in the melt transfer method, a transfer sheet having a heat-meltable ink layer (low melting point) mainly composed of a coloring material such as a pigment or a dye and a binder such as wax on a support is used. A method of forming an image by heating a heating device such as a thermal head according to image information and melting the ink layer, thereby releasing the ink layer from the base material and attaching the ink layer on the image receiving sheet. It is. The image formed by the melt transfer method has high density and excellent sharpness,
It is suitable for recording binary images such as characters and line drawings. Further, a color image can be formed by superimposing an image on an image receiving sheet using a thermal transfer sheet made of yellow, magenta, cyan, and black.
Japanese Patent Publication No. 63-65029 discloses an example of such a thermal transfer sheet for forming a color image.

However, in the case of the thermal transfer sheet described in JP-B-63-65029, since a low-melting crystalline wax is used as a binder for the ink layer, the resolving power tends to decrease due to ink bleeding. . In addition, the fixing strength of the transferred image is low, and if the image portion is rubbed strongly by hand, the image portion is removed.

Various proposals have been made as a method for solving such development. For example, JP-A-61-24459
No. 2 proposes a heat-sensitive transfer sheet having a heat-sensitive ink layer comprising 65% or more of an amorphous polymer, a release material and a colorant. However, Japanese Patent Application Laid-Open No.
The thermal transfer sheet described in Japanese Patent Publication No. 244592 also contains a crystalline wax, and therefore, the fixing strength of the portion where the superimposed printing of each color is performed is insufficient.

Further, although the fusion transfer method is capable of forming a color image, it has a problem that the gradation expression suitability and resolution are extremely low, and as a result, high image quality cannot be expected.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an excellent image having high resolution, rich gradation expression by area gradation, excellent image durability, and high optical density of the image. An object of the present invention is to provide an image forming body and an image-attached card provided with the above.

[0010]

Means for Solving the Problems The invention described in claim 1 is:
At least on the support, an image formed of dots of a plurality of colors of ink, and a transparent layer provided so as to cover the image, the ink is a color pigment, an amorphous organic polymer, In addition, the present invention provides an image forming body containing colorless or light-colored fine particles as a main component, and having a dot thickness in the range of 0.2 to 1.0 μm.

According to a second aspect of the present invention, the image forming body according to the first aspect is a booklet-shaped passport, and the support is a cover, a back cover, or a bound page of the passport. An image forming body characterized in that it is any one of the above.

According to a third aspect of the present invention, there is provided an image forming body characterized in that the image forming body according to the first aspect is a seal-shaped or strip-shaped visa. Here the visa is
For example, it is used by pasting or binding to any of the cover, back cover, or bound page of a passport.

According to a fourth aspect of the present invention, the image forming body according to the first aspect is a booklet, and the support is any one of a front cover, a back cover, and a bound page of the booklet port. An image forming body characterized in that: Here, the booklet is, for example, a bankbook or a post office bankbook.

According to a fifth aspect of the present invention, there is provided at least an image formed by dots of a plurality of colors of ink on a support, and a transparent layer provided so as to cover the image. , A color pigment, an amorphous organic polymer, and colorless or light-colored fine particles as main components.
Provided is a card with an image, which is in the range of 2 to 1.0 μm.

On the support, in addition to the image and the transparent layer, an appropriate material is used at an appropriate place for any purpose.
Other images and other layers may be provided as appropriate. (For example, an anchor layer that increases the adhesive strength between layers, a resistance enhancement layer that increases resistance, a decoration effect layer that imparts decorativeness, or a forgery prevention layer described below, etc.) Further, the “fine particles” referred to herein serve as fillers. The expression “colorless or light color” means that the color and density of the image by the ink are not substantially affected. The transparent layer is mainly composed of a resin (in some cases, a filler is also used), and the image formed by the dots of the plurality of colors of ink below the transparent layer can be viewed. This image also serves to protect the image from mechanical damage such as rubbing and scratching, and chemical damage due to solvents and the like.

The area where the transparent layer is formed on the card with the image may be only on the image formed by the dots of the inks of a plurality of colors. Is also formed in an area of other information (eg, characters / codes / patterns indicating the affiliation of the owner of the owner with a binary image, etc.) provided in addition to the image according to (1). This is because, in addition to protecting the other information referred to here from mechanical or chemical damage, depending on the use of the image card, it is very important information in security measures, so the above-mentioned case is not the same. Similarly, countermeasures against forgery and tampering can be strengthened.

Further, more preferably, a transparent layer is provided on the entire surface of the card with the image. By providing a transparent layer, the image and other information can be protected from mechanical or chemical damage, used for security measures, and it is easy to add some decorativeness, but the transparent layer In particular, the degree of freedom in designing security measures and decorativeness is increased.

According to a sixth aspect of the present invention, there is provided the card with an image according to the fifth aspect, wherein the plural colors of ink include at least three colors of yellow, magenta, and cyan. If the image is formed by applying thermal transfer, for example, three colors of cyan, magenta, and yellow, or four colors of cyan, magenta, yellow, and black are printed on the support in the longitudinal direction. It is convenient to use a thermal transfer recording medium (ink ribbon) which is repeatedly arranged side by side along the line. Although it is somewhat inconvenient, the ink ribbon coated with a single color may be replaced with a single-color ink ribbon instead of the color-separated ribbons if the required color (cyan, magenta, and yellow are required). Can be used to form an image.

According to a seventh aspect of the present invention, there is provided the card with an image according to any one of the fifth and sixth aspects, wherein the ink contains 80% by weight or more of the coloring pigment as an organic pigment. .

[0020] In the invention described in claim 8, the color pigment is:
The card with an image according to any one of claims 5 to 7, wherein the average particle diameter is in a range of 50 to 500 nm.

According to a ninth aspect of the present invention, the colorless or light-colored fine particles have an average particle diameter in a range of 100 to 300 nm. provide.

According to a tenth aspect of the present invention, the ink comprises:
The card with an image according to any one of claims 5 to 9, wherein the particle size distribution of the color pigment is such that the ratio of the color pigment having a particle size exceeding 1 µm is 10% or less.

[0023] The invention according to claim 11 is characterized in that the width of the particle size distribution of the colorless or light-colored fine particles is narrower than the width of the particle size distribution of the color pigment. 10. A card with an image according to any one of 10 above.

According to a twelfth aspect of the present invention, in the thermal transfer recording layer, the mixing ratio of the color pigment, the amorphous organic polymer, and the colorless or light-colored fine particles is 20 to 60.
12. The method according to claim 5, wherein the amorphous organic polymer is in a range of 40 to 80 parts by weight, and the fine particles are in a range of 1 to 30 parts by weight. Provide cards with images. However, these coloring pigments,
The parts by weight referred to in the mixing ratio of the amorphous organic polymer and the colorless or light-colored fine particles are values relating to solid content.

When other compositions are added to the thermal transfer recording layer, specific examples include dispersants such as surfactants. The mixing ratio at that time is such that the total amount of the solid content of the color pigment, the amorphous organic polymer, and the colorless or pale-colored fine particles is 100 parts by weight, and the other components to be added thereto are 0.1 parts by weight.
It is 1 to 10 parts by weight. If the weight ratio of the other composition is too small, the effect of the other composition will not be sufficiently exhibited.On the contrary, if the weight ratio of the other composition is too large, all of the initial problems of the present invention will be sufficient. It is difficult to solve to meet.

If the other composition is a dispersant, its role is to achieve the following effects. That is, in order to provide the thermal transfer recording layer on the support, generally, a composition having an appropriate amount of the composition forming the thermal transfer recording layer,
An appropriate amount of a suitable solvent having volatility is added to form a coating liquid, which is applied to an appropriate place on the support in an appropriate amount, and then the solvent component is volatilized. In the case where a problem that seems to be caused by undesired aggregation of the color pigments and fine particles occurs, by adding a dispersant to the coating liquid, it is possible to impart preferable dispersibility to the color pigments and the fine particles. It is possible to solve the problem which is considered to be caused by the aggregation.

According to a thirteenth aspect of the present invention, an intermediate layer containing an amorphous organic polymer of the same kind as the amorphous organic polymer of the ink is provided on the support. The image-attached card according to any one of claims 5 to 12, wherein the card is provided between an intermediate layer and the transparent layer.

The invention according to claim 14 is characterized in that the amorphous organic polymer contains at least an epoxy resin having a softening point in the range of 70 to 150 ° C. Provided is a card with an image described in Crab.

According to a fifteenth aspect of the present invention, there is provided the card with an image according to any one of the fifth to fourteenth aspects, wherein the card with the image is an IC card.

According to a sixteenth aspect of the present invention, there is provided the card with an image according to any one of the fifth to fourteenth aspects, wherein the card with the image is a contactless card.

According to a seventeenth aspect of the present invention, there is provided the card with image according to any one of claims 5 to 14, wherein the card with image is a memory card. In the present invention, a memory card refers to a card having a memory function but not having a cpu.

The invention as set forth in claim 18 provides the card with image according to any one of claims 5 to 14, wherein the card with image is a hybrid card. In the present invention, the hybrid card is a function of an IC card that performs data communication in a contact manner and a function of a contactless card that performs data communication in a non-contact manner.
Refers to a card that has both functions.

According to a nineteenth aspect of the present invention, there is provided the card with image according to any one of claims 5 to 14, wherein the card with image is a rewritable card.

According to a twentieth aspect of the present invention, there is provided the card with an image according to any one of the fifth to fourteenth aspects, wherein the card with the image is a magnetic recording card.

It is to be noted that the card with the image is appropriately selected from at least two or more functions of an IC card, a contactless card, a memory card, a hybrid card, a rewritable card, or a magnetic recording card, and It can also be configured to be prepared for a single card. According to this, a very convenient function can be exhibited for various uses, which is more preferable.

Of these image-attached cards, for example,
IC cards, contactless cards, memory cards,
In the case of a card with an image having a function of recording information by a memory or a magnetic information recording layer, such as a hybrid card or a magnetic recording card, a person attempting to use the card with the image is It is very useful in determining if you are / has been a legitimate owner.

That is, it is very useful in terms of security, that is, countermeasures against tampering and forgery, especially countermeasures against tampering. That is, an image formed by dots of the plurality of colors of ink provided so as to be visible from the outside of the card with an image according to the present invention (particularly, a face image of a proper owner of the card with the image, an autograph, a fingerprint, or the like) If the information is unique to each person and is imaged, the information of the image should be recorded in the memory of the card with the image or the magnetic information recording layer, even if the image is tampered with. If
The information in the memory or the magnetic information recording layer is
By displaying the image as a visible image by an appropriate means, by comparing the image with the image provided so as to be visible from the outside of the image-equipped card, it is determined whether the card is an authorized owner of the image-equipped card. / No can be easily determined.

In particular, a card with an image having the function of recording information using these memories or the magnetic information recording layer and a card with an image combining the functions of recording information and displaying the visibility of a rewritable card are provided. In such a case, there is no need to separately provide a means for displaying the information in the memory or the magnetic information recording layer as a visible image as described above, which is more convenient.

According to a twenty-first aspect of the present invention, a second image formed by using at least one of a hologram, a diffraction grating, a fluorescent agent, and a magnetic material and dots of the plurality of colors of ink are formed. 21. The card with an image according to claim 5, wherein the image is formed so as to be visible on the same side of the support.

It should be noted that the second image may be either visually observable or difficult to observe under the condition. In other words, the second image under the state may be easily recognizable by visual observation itself, or may be difficult to recognize by visual observation. However, a fluorescent agent that emits fluorescence by UV irradiation or the like, a magnetic material having magnetism, and a second image in the case of using any of these,
It is preferable from the viewpoint of security measures that it is difficult to visually recognize under the condition.

By providing this second image in the same plane as the above-mentioned image, the decorativeness is enhanced, and
The effect of suppressing forgery and tampering or facilitating detection of forgery and tampering can be obtained. The reasons why counterfeiting and tampering are difficult, or that counterfeiting and tampering are easy to detect are:
The second image is generally derived from the need for advanced manufacturing technology and expensive equipment. (1) If a forgery is attempted, the technology and profitability will be a bottleneck, so such unauthorized It is easy to deter the action. (2) It is a fundamental idea to falsify the image with the ink without damaging the second image even if the falsification is attempted.
If the damage of the image is to be repaired, the technology and profitability will still be a bottleneck, and it is easy to suppress such misconduct, and (3) If the second image is reproduced or repaired, If not, the second image supposed to be formed on the image-attached card does not exist there, and it is possible to visually discriminate the second image, so that forgery and tampering can be easily found.

The ink forming an image with dots of a plurality of colors of the card with an image according to the present invention is very preferably an ink containing no crystalline wax. This will be described later.

As the ink of the card with an image according to the present invention in which an image is formed by dots of a plurality of colors, an ink containing a coloring pigment, an amorphous organic polymer, and fine particles is used. Although various materials can be used as the fine particles, silica is particularly preferable. This will also be described later.

The image-bearing card according to the present invention is not particularly limited as long as an image is formed on the card, but particularly preferable are, for example, an IC card, a contactless card, a hybrid card, and a memory. Card, rewrite card, magnetic card etc. or (in terms of use) cash card, credit card, (card-like) license, (card-like) passport, (card-like) health insurance card, (national card or Local government cards (such as prefectural cards), ID cards, membership cards, and the like. These examples are particularly suitable for the present invention because they require particularly high security and can use an image as a material for determining whether or not the card is a valid owner (or user).

FIG. 7 is a conceptual diagram of a card with an image according to the present invention, particularly showing a state in which dots of a plurality of colors of ink are overlapped. In addition, the card with the image according to the present invention includes, in addition to the multicolored image, information (eg, first and last name, affiliation, date of birth, number, code, etc.) concerning the proper owner (or user) of the card with the image. , Etc.) may be used to form a binary image (most commonly using black ink) or to record the same information using embossing.

[0046]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a method for forming an image on a card with an image according to the present invention, thermal transfer is preferable, and it is particularly preferable to use a special thermal transfer recording medium (ink ribbon). Thermal transfer using a special thermal transfer recording medium is the following method. This transfer phenomenon is caused by the fact that heat is applied to the thermal transfer recording medium by a heating medium such as a thermal head, so that the amorphous organic polymer as a binder material in the thermal transfer recording layer is melted, semi-melted, or softened (preferably). Is semi-melted or softened as described later), and peels off from the base sheet of the thermal transfer recording medium and develops adhesiveness, so that an image receiving sheet (an intermediate image receiving sheet as an intermediate image carrier, or a support of a card) The image is recorded by thermal bonding on the body). Therefore, when printing is performed by overlapping at least two or more colors, a clear print without blurring of the ink can be obtained. Further, the transferred recorded image has excellent mechanical strength.

In order to obtain an image with high resolution and rich gradation expression by area gradation, especially when heated by a heating medium such as a thermal head, an amorphous material which is a binder material is used. Organic polymer (rather than melting)
A transfer mechanism in which the heat transfer recording layer is partially melted or softened, and a part of the thermal transfer recording layer is peeled off from the substrate in a layered manner, and is thermally bonded to the image receiving sheet side is preferable. In order to achieve such excellent image quality transfer, for example, not only the composition ratio of the materials in the thermal transfer recording layer, the material selection of the amorphous organic polymer, but also the thickness of the thermal transfer recording layer is important. It is.

Hereinafter, a detailed description will be given of thermal transfer, which is a preferred technical example when forming an image on a card with an image according to the present invention, and a particularly preferred example of a thermal transfer recording medium. FIG. 1 shows an example of a thermal transfer recording medium (1) suitable for forming an image on a card with an image according to the present invention provided with a thermal transfer recording layer (3) on a support (2).

As the support (2) that can be used for the above-mentioned thermal transfer recording medium, those generally known for sublimation transfer type and melt transfer type can also be used. Specific examples include polyethylene terephthalate, polyethylene naphthalate, polypropylene, cellophane, polycarbonate, polyvinyl chloride, polystyrene, polyimide, nylon, plastic films such as polyvinylidene chloride, condenser paper, and paper such as paraffin paper. However, a polyester film is particularly preferred. The thickness of the support (2) is 2 to 50 μm, more preferably 2 to 16 μm.
The thermal transfer recording layer (3) is composed of a color pigment, an amorphous organic polymer (eg, epoxy resin), and colorless or light-colored fine particles.

The amorphous organic polymer contained in the thermal transfer recording layer (3) includes, for example, butyral resin, polyamide resin, polyester resin, epoxy resin, acrylic resin, and vinyl-based monomers such as vinyl chloride and vinyl acetate. It is possible to use a monomer alone or a copolymer with another monomer, or the like. Among them, an epoxy resin is preferable, and a resin having a softening point in the range of 70 ° C. to 150 ° C. is used in consideration of printing aptitude for a heat medium such as a thermal head and durability of an image after transfer recording. .

Generally, the thermal conditions for thermal transfer using a thermal head are usually 180 to 400 ° C. for several milliseconds. Further, in order to perform thermal transfer recording as described above, it is necessary to heat the amorphous organic polymer until it melts, more preferably until it is semi-melted or softened (depending on the thermal transfer recording layer of the thermal transfer recording medium). There is.

Therefore, in consideration of the amount of heat supplied from the thermal head and, for example, in the case of an epoxy resin, a change in state due to the heat of the epoxy resin, the upper limit of the melting point is 150 ° C.
Becomes If a resin exceeding the upper limit is used, more energy is required for transfer, and even the problem that the life of the thermal head is extremely shortened may be caused. Further, the lower limit is set to 70 ° C. in consideration of the holding stability of the image after the transfer recording, and if the melting point is 70 ° C.
This is because, if an epoxy resin less than the above is used, phenomena such as the occurrence of tailing when rubbed by hand occur.

The properties of the epoxy resin, which is a typical example of the amorphous organic polymer used as one of the main materials for the thermal transfer recording layer of the present invention, are particularly preferably epoxy equivalent (1 gram of epoxy resin). (The number of grams of the resin containing a group) is from 600 to 5,000, and a characteristic of a molecular weight of from 800 to 5,000 is desired.

If the epoxy equivalent of this epoxy resin is
If the value is lower than the lower limit (less than 600), the durability of the image to rubbing is not sufficient, and if the image is rubbed by hand, tailing tends to occur in the transferred image, which is not preferable. Conversely, if the epoxy equivalent is higher than the upper limit (5,000)
In this case, the thermal energy required for the thermal transfer is too large, and the life of the thermal head is shortened. Also, the sensitivity of the thermal transfer is low. It is not preferable because it is unsuitable for the purpose of recording.

Then, the molecular weight of this epoxy resin is
If the value is lower than the lower limit (less than 800), the durability of the image to rubbing is not sufficient, and if the image is rubbed by hand, tailing tends to occur in the transferred image, which is not preferable. Conversely, if the molecular weight is higher than the above upper limit (more than 5,000), the thermal energy required for thermal transfer is too large, and the life of the thermal head is shortened. However, since the thermal transfer sensitivity is low, it is not suitable for use in thermal transfer recording of an image at high speed, which is not preferable.

The most preferred epoxy resin in the present invention is one in which all the properties of the softening point, epoxy equivalent and molecular weight are simultaneously within the above respective ranges. This case is preferable because high effects can be obtained particularly with respect to image transferability and durability.

For the above reasons, the melting point is 70-150 ° C.
Epoxy equivalent of 600-5000 and molecular weight of 800
An epoxy resin in the range of ~ 5000 is selected. Examples of such an epoxy resin include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, resorcinol diglycidyl ether,
Glycidyl ether type epoxy resins such as cresol novolac polyglycidyl ether, tetrabromobisphenol A diglycidyl ether, bisphenol hexafluoroacetone glycidyl ether, glycidyl ester type epoxy resins such as phthalic acid diglycidyl ester, dimer acid diglycidyl ester, and triglycidyl Glycidylamine type epoxy resins such as isocyanurate, tetraglycidylaminodiphenylmethane, and tetraglycidylmethaximendiamine, and aliphatic epoxy resins such as hexahydrobisphenol A diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl glycol diglycidyl ether. Can be mentioned. Any of these may be selected.

The colorless or light-colored fine particles contained in the thermal transfer recording layer (3) are used to improve the transferability during thermal transfer, more specifically, the dot shape on which a transferred image is formed, and the gradation reproducibility. The use of a colorless or light-colored component is a necessary component in order not to impair the color development of a colored image formed by thermal transfer. Examples of such colorless or light-colored fine particles include silica, calcium carbonate, kaolin, clay, starch, zinc oxide, Teflon (registered trademark) powder, polyethylene powder, polymethyl methacrylate resin beads, polyurethane resin beads, benzoguanamine and melamine. Resin beads and the like can be mentioned. Among the above, silica fine particles are particularly preferred.

As the color pigment contained in the thermal transfer recording layer (3), various known pigments can be used. As an example, carbon black is preferable for black single-color printing, and pigments forming yellow, magenta, and cyan, and four-color pigments obtained by adding black to these three-color pigments are used for multi-color printing. These pigments can be used alone or in combination of two or more.

The composition of the composition for forming the thermal transfer recording layer (3) is such that the solid content of the composition is such that
60 parts by weight, 40 to 80 parts by weight of an amorphous organic polymer, and 1 to 30 parts by weight of colorless or pale-colored fine particles. When the amount of the coloring pigment is less than the above range, a desired printing density cannot be obtained, and when the amount is too large, the film strength is unfavorably reduced. Also, if the amount of the amorphous organic polymer (for example, epoxy resin) is less than the above range, the film strength is unfavorably reduced, and if the amount is too large, there is a problem of transferability. It is not preferable because the dot shape on which an image is formed and the gradation reproducibility deteriorate.
If the number of colorless fine particles is smaller than the above range, the transferability problem, specifically, the dot shape on which the transferred image is formed, the gradation reproducibility, etc. are not preferable, and if it is large, Does not provide good fluidity of the ink. In the thermal transfer recording layer, various additives can be further added to these materials as needed. The amount of addition is preferably 10 parts by weight or less based on 100 parts by weight (solid content) of the composition for forming the thermal transfer recording layer.

The method for producing a thermal transfer recording medium according to the present invention comprises the steps of: applying a composition obtained by dispersing or dissolving a colorant, an epoxy resin and colorless fine particles in a solvent on a substrate such as coated paper or plastic; It is formed by applying a solvent coat method such as a blade coat, an air knife coat, a gravure coat, a roll coat and the like, and drying to form a thermal transfer recording layer.

The thickness of the thermal transfer recording layer (3) is from 0.2 to
1.0 μm is desirable. When the film thickness is less than 0.2 μm, it is difficult to obtain a sufficient density, and when the film thickness is more than 1.0 μm, it becomes difficult to perform transfer according to the heat-generating portion of the thermal head. The gradation reproducibility is inferior.

The thermal transfer recording layer (3) of the support (2)
When the thermal transfer recording layer (3) is transferred to the image receiving sheet by applying heat from the side not provided with the thermal transfer recording layer (3), the thermal head adheres to the support (2) and the thermal transfer recording medium (1) In order to prevent smooth running, it is desirable to provide a back coat layer (4) on the side of the support (2) where the thermal transfer recording layer (3) is not provided.

Examples of the material used for the back coat layer (4) include nitrocellulose, polyester resin, acrylic resin, vinyl resin and the like containing silicon oil, or silicon-modified resin. it can. Further, a crosslinking agent may be used in combination for the purpose of improving heat resistance. The coating thickness when providing the back coat layer (4) is preferably about 0.1 to 4 μm.

An image receiving sheet used for forming an image by using the above-described thermal transfer recording medium (1) (an intermediate sheet provided with a transferable image receiving layer peeled off from the base material and transferred to the transfer receiving body side) As the image receiving sheet), for example, paper such as high-quality paper, coated paper, a plastic film such as a polyester film, a polyvinyl chloride film, a polypropylene film, or a paper or a plastic film as a base material, on which transfer can be performed As described above. In general, it is preferable to use the same or similar material as the amorphous organic polymer for the image receiving layer used here.

That is, if the amorphous organic polymer of the thermal transfer recording layer is, for example, an epoxy resin, it is preferable to use an epoxy resin also as a main material of the image receiving layer. That is, by using the same or the same kind of amorphous organic polymer as the material of the image receiving layer, the thermal transfer recording layer of the thermal transfer recording medium is not sufficiently melted, semi-melted, or softened at the time of thermal transfer. Due to the heat at this time, the thermal transfer recording layer and the image receiving layer adhere well, and printing is performed by expressing sufficient foil breakage, so that the transferability problem, specifically, the transfer image is formed. The dot shape, gradation reproducibility and the like are improved. Further, the formed image has excellent image resistance such as abrasion resistance and scratch resistance.

When it is difficult to form an image directly on a sheet on which an image is to be formed, an image may be formed once on the image receiving sheet, and then the transferred image may be retransferred to a final sheet. . Such an indirect transfer method not only widens the selectivity of the final sheet, but also provides a protective layer on the final transfer image by providing a protective layer on the image receiving sheet, thereby improving the image resistance and improving image resistance. By providing a security layer such as a hologram forming layer on the sheet, it is possible to improve the security of the final transfer image.

The means for applying thermal energy used to obtain a gradation image expression by area gradation using the thermal transfer recording medium of the present invention as described above and the image receiving sheet as described above may be any of conventionally known applying means. Can be used, and a gradation image can be obtained by controlling the heat energy.

The average particle size of the color pigment or the colorless or light-colored fine particles is determined, for example, by using an auto-sizer based on a light scattering system (AUTOSIZER: commercially available from MARVERRUN), a Coulter counter method, processing of SEM observation images, and the like. Can be measured.

[0070]

Next, the present invention will be described more specifically with reference to examples. In the following description, “parts” or “%” is based on weight unless otherwise specified.

Example 1 First, an ink composition for a thermal transfer recording layer having the following composition was prepared.

(Cyan ink) Phthalocyanine blue 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C, epoxy equivalent 1750-2200, molecular weight 2900 colorless fine particles (silica: Aerosil manufactured by Nippon Aerosil Co., Ltd.) R972) 4 parts Methyl ethyl ketone 67 parts (magenta ink) Carmine 6B 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C, epoxy equivalent 1750-2200, molecular weight 2900 colorless fine particles ( Silica: Aerosil R972 manufactured by Nippon Aerosil Co., Ltd. 4 parts Methyl ethyl ketone 67 parts (yellow ink) Disazo Yellow 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C, Epoxy Eq from 1750 to 2200, the molecular weight 2900 colorless microparticles (silica: Nippon Aerosil Aerosil R972) ... 4 parts Methylethyl ketone 67 parts

The ink for a thermal transfer recording layer having the above formulation was applied to a 5.4 μm-thick polyethylene terephthalate film having a heat-resistant rear surface and dried so as to have a dry film thickness of 0.7 μm. A thermal transfer recording medium was obtained.

Next, the following inks were sequentially applied to a 25 μm polyester film (PET) and dried to form a release layer (dry thickness: 1 μm) and an image receiving layer (dry thickness: 5 μm). A laminated image receiving sheet (intermediate image receiving sheet) was obtained.

(Ink for release layer) Acrylic resin ... 20 parts Methyl ethyl ketone ... 40 parts Toluene ... 40 parts (Image receiving layer ink) Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) ... 30 parts * Softening point 128 ° C, epoxy equivalent 1750-2200, molecular weight 2900 methyl ethyl ketone ... 70 parts

The thermal transfer recording layer surface of the thus obtained cyan thermal transfer recording medium was superimposed on the image receiving sheet, and using a thermal head, a cyan image having an area gradation corresponding to the heat generating portion of the thermal head was obtained. Next, using a magenta thermal transfer recording medium, a magenta image based on area gradation was formed on an image receiving sheet on which a cyan image was formed in the same manner as for cyan. Similarly, a yellow image was formed, and a color image consisting only of area gradation was formed on the image receiving sheet.

Comparative Example 1 The following sublimation transfer type ink composition was prepared as an ink for a thermal transfer recording layer. (Cyan ink) C.I. I. Solvent Blue 63 5 parts Butyral resin (BX-1 manufactured by Sekisui Chemical Co., Ltd.) 5 parts Methyl ethyl ketone 60 parts Toluene 30 parts (magenta ink) C.I. I. Disperse Red 60: 5 parts Butyral resin (BX-1 manufactured by Sekisui Chemical Co., Ltd.): 5 parts Methyl ethyl ketone: 60 parts Toluene: 30 parts (yellow ink) I. Disperse Yellow 201 5 parts Butyral resin (BX-1 manufactured by Sekisui Chemical Co., Ltd.) 5 parts Methyl ethyl ketone 60 parts Toluene 30 parts

The ink for a thermal transfer recording layer having the above formulation was applied to a 5.4 μm-thick polyethylene terephthalate film having a heat-treated rear surface and dried so as to have a dry film thickness of 1.0 μm. Was obtained.

Next, the following inks were sequentially applied on a 25 μm polyester film (PET) and dried to form a release layer (dry thickness 1 μm) and an image receiving layer (dry thickness 4 μm).
μm), followed by aging at 45 ° C. for 1 week to obtain an image receiving sheet (intermediate image receiving sheet).

(Release layer ink) Acrylic resin ... 20 parts Methyl ethyl ketone ... 40 parts Toluene ... 40 parts (Ink for dye receiving layer) Acetal resin ... 10 parts Vinyl chloride-vinyl acetate copolymer resin ... 10 parts Silicone oil ... 2 parts Isocyanate resin 3 parts Methyl ethyl ketone 50 parts Toluene 25 parts

The surface of the thermal transfer recording layer of the obtained thermal transfer recording medium was superimposed on the surface of the dye receiving layer of the image receiving sheet, and images were formed in the order of yellow, magenta, and cyan using a thermal head to obtain a color image.

Comparative Example 2 A thermal transfer recording medium was prepared in the same manner as in Example 1 except that the dry film thickness of the ink for the thermal transfer recording layer was changed to 1.2 μm for each of cyan, magenta and yellow. Was formed.

Comparative Example 3 A thermal transfer recording medium was prepared and a color image was formed in the same manner as in Example 1, except that the ink for the thermal transfer recording layer was changed to the following formulation.

(Cyan Ink) Phthalocyanine Blue 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C, epoxy equivalent 1750-2200, molecular weight 2900 methyl ethyl ketone 71 parts (magenta ink) Carmine 6B 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C, epoxy equivalent 1750-2200, molecular weight 2900 methyl ethyl ketone 71 parts (yellow ink) Disazo Yellow 9 parts Epoxy resin (oil) Shell Epoxy: Epicoat 1007) 20 parts * Softening point 128 ° C Epoxy equivalent 1750-2200 Molecular weight 2900 Methyl ethyl ketone 71 parts Phthalocyanine blue 10 parts

Comparative Example 4 A thermal transfer recording medium was prepared and a color image was formed in the same manner as in Example 1, except that the ink for the thermal transfer recording layer was changed to the following formulation.

(Cyan ink) Phthalocyanine blue: 9 parts Epoxy resin (manufactured by Yuka Shell Epoxy: Epicoat 1001): 20 parts * Softening point: 64 ° C. Epoxy equivalent: 450-500 Molecular weight: 900 Colorless fine particles (silica: Aerosil R972 manufactured by Nippon Aerosil) ... 4 parts Methyl ethyl ketone ... 67 parts (magenta ink) Carmine 6B ... 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1001) ... 20 parts * Softening point 64 ° C Epoxy equivalent 450-500 Molecular weight 900 Colorless fine particles (silica: Nippon Aerosil) Aerosil R972) 4 parts Methyl ethyl ketone 67 parts (yellow ink) Disazo Yellow 9 parts Epoxy resin (Yuika Shell Epoxy: Epicoat 1001) 20 parts * Softening point 64 ° C Epoxy equivalent 450-500 molecules 900 Colorless fine particles (silica: Nippon Aerosil Aerosil R972) ... 4 parts Methylethyl ketone 67 parts

Comparative Example 5 A thermal transfer recording medium was prepared and a color image was formed in the same manner as in Example 1 except that the ink for the thermal transfer recording layer was changed to the following formulation.

(Cyan Ink) Phthalocyanine Blue 9 parts Epoxy resin (manufactured by Yuka Shell Epoxy: Epicoat 1010) 20 parts * Softening point 169 ° C. Epoxy equivalent 3000-5000 molecular weight 5500 Colorless fine particles (silica: Aerosil R972 manufactured by Nippon Aerosil Co., Ltd.) ... 4 parts Methyl ethyl ketone ... 67 parts (magenta ink) Carmine 6B ... 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1010) ... 20 parts * Softening point 169 ° C Epoxy equivalent 3000-5000 Molecular weight 5500 Colorless fine particles (silica: Nippon Aerosil) Aerosil R972) 4 parts Methyl ethyl ketone 67 parts (yellow ink) Disazo Yellow 9 parts Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1010) 20 parts * Softening point 169 ° C Epoxy equivalent 3 00-5000 molecular weight 5500 colorless microparticles (silica: Nippon Aerosil Aerosil R972) ... 4 parts Methylethyl ketone 67 parts

Example 1 and Comparative Examples 1, 2, 3, 3,
By superimposing the images obtained in steps 4 and 5 on the support of the card and applying heat and pressure to transfer the image together with the image receiving layer,
For a card with an image in which a transparent image-receiving layer (that is, a transparent layer also serving as a protective layer) is formed so as to cover the image,
Evaluation was made on image gradation, light fastness, fixability (which also affects security), and high-density balance. Table 1 shows the results.

[0090]

[Table 1]

Image gradation: ○: The produced color image is faithfully reproduced from the highlight portion to the shadow portion. ×: The reproducibility from the highlight portion to the shadow portion is insufficient. Light fastness: The color image surface was irradiated with a xenon fade meter for 80 hours, and the fading rate was measured. ：: Fading rate of 5% or less ×: Fading rate of 5% or more Fixing property: Degree of tailing of the image area when the color image surface is rubbed with a nail with a normal force. ：: no change ×: dirt around the image area High density density balance: difference in optical density between cyan, magenta and yellow color components of full solid image density (three-color superimposed black density) ：: within 10% x: 10 %that's all

As shown in the table, in the thermosensitive recording medium according to the present invention (Example 1), a color image produced in gradation reproducibility is faithfully reproduced from a highlight portion to a shadow portion.
An excellent thermal transfer recording medium having the durability of an image after recording can be obtained, and the object of the present invention has been achieved.

Example 2 In Example 1, the following black ink was added to three colors of cyan, magenta, and yellow as the ink composition for the thermal transfer recording layer, and a color image was formed by mixing four colors.

(Black ink) Carbon black: 9 parts Epoxy resin (manufactured by Yuka Shell Epoxy: Epicoat 1007): 20 parts * Epoxy equivalent: 1750-2200 Softening point: 128 ° C. Molecular weight: 2900 Colorless fine particles (silica: Aerosil R972 manufactured by Nippon Aerosil Co., Ltd.) ... 4 parts Methyl ethyl ketone ... 67 parts

The obtained image is superimposed on the support of the card, and the image is transferred together with the image receiving layer by applying heat and pressure, whereby the transparent image receiving layer (that is, the transparent layer also serving as a protective layer) forms the image. It was confirmed that the card with the image formed so as to cover had the same performance as that of Example 1.

Example 3 In Example 1, a color image was created by mixing three colors of cyan, magenta and yellow, and a binary image of characters and bar codes was created in black. In the same manner as in Example 1, the obtained image is superimposed on the support of the card, and the image is transferred together with the image receiving layer by applying heat and pressure to form a transparent image receiving layer (that is, a transparent layer which also serves as a protective layer). ) Was evaluated for a card with an image formed so as to cover the image, and the obtained image had excellent resistance to characters and barcodes in addition to the performance in Example 1. It was confirmed that. It was confirmed that the obtained image had excellent resistance to characters and barcode portions in addition to the performance of Example 1.

Example 4 Using the thermal transfer recording medium obtained in Example 1, an image was formed on the following image receiving sheet.

(Construction of Image-Receiving Sheet) Each of the following prescription inks was sequentially applied to a 25 μm polyester film and dried to obtain an image-receiving sheet in which a release layer and an image-receiving layer were sequentially laminated.

(Ink for release layer) Acrylic resin 20 parts Methyl ethyl ketone 40 parts Toluene 40 parts

(Ink for image receiving layer) Epoxy resin (made by Yuka Shell Epoxy: Epicoat 1007): 30 parts * Epoxy equivalent: 1750-2200 Softening point: 128 ° C Molecular weight: 2900 Methyl ethyl ketone: 70 parts

When the image-receiving sheet on which the image was formed was overlapped with the sheet for the final product, thermal transfer was performed from the back of the image-receiving sheet with a heat roller, and only the polyester film was peeled off. Thus, a card with an image, in which the transparent layer that fulfills the function, was formed so as to cover the image, was obtained.

Example 5 Using the thermal transfer recording medium obtained in Example 1, an image was formed on the following image receiving sheet (intermediate image receiving sheet).

(Construction of Image Receiving Sheet) The following ink for a release layer and ink for a hologram formation layer were sequentially applied to a 25 μm polyester film and dried to obtain a release layer and a hologram formation layer. A hologram was formed on the surface of the substrate by using an uneven shape.

(Release layer ink) Acrylic resin ... 20 parts Methyl ethyl ketone ... 40 parts Toluene ... 40 parts (Hologram formation layer ink) Vinyl chloride-vinyl acetate copolymer ... 20 parts Urethane resin ... 15 parts Methyl ethyl ketone ... 70 parts Toluene ... 30 copies

Further, ZnS as a transparent thin film layer was provided on the surface of the hologram forming layer by vapor deposition, and the following ink for an image receiving layer was applied and dried to laminate the image receiving layers, thereby obtaining an image receiving sheet.

(Ink for Image Receiving Layer) Epoxy resin (manufactured by Yuka Shell Epoxy: Epicoat 1007): 20 parts * Epoxy equivalent: 1750-2200, softening point: 128 ° C., molecular weight: 2900 Urethane resin: 10 parts Methyl ethyl ketone: 70 parts

The image-receiving sheet on which the image was formed was overlapped with a final product sheet having an ultraviolet light emitting fluorescent agent printed on the surface, and thermal transfer was performed with a heat roller from the back of the image-receiving sheet.
After peeling off only the polyester film,
It was possible to obtain a card with an image in which a transparent layer (a transparent layer including an image receiving layer and a hologram forming layer and also acting as a protective layer as a whole) was formed so as to cover the image.

The obtained image-attached card had a hologram image that was useful as a security measure (a measure against forgery and tampering), and had high security. The results of Examples 2 to 5 are also shown in Table 1 above.

[0109]

According to the present invention, an image formed by dots of a plurality of colors of ink has a high resolution, a rich gradation expression by area gradation, and an excellent image durability. In addition, it was possible to provide an image forming body and an image-attached card having an excellent image having a high optical density of the image. In addition, if such information is applied to information unique to the authorized owner (or authorized user) of the card with the image (or an image of a face photograph, fingerprint, autograph, retina, etc.), the security is increased. An image forming body and a card with an image, which also have a material for countermeasures.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram using a schematic cross-sectional view of a preferred example of a thermal transfer recording medium when thermal transfer recording is used when forming an image on a card with an image according to the present invention. (Y indicates yellow, M indicates magenta, and C indicates cyan.)

FIG. 2 is an explanatory view using a schematic cross-sectional view of another preferred example of a thermal transfer recording medium when thermal transfer recording is used when forming an image on a card with an image according to the present invention. (Y indicates yellow, M indicates magenta, and C indicates cyan.)

FIG. 3 shows the degree of dispersion of the cyan pigment used in Example 1.
(The horizontal axis represents the particle diameter [nm], and the vertical axis represents the ratio [%] of particles having each particle diameter.)

FIG. 4 shows the degree of dispersion of the magenta pigment used in Example 1. (The horizontal axis represents the particle diameter [nm], and the vertical axis represents the ratio [%] of particles having each particle diameter.)

FIG. 5 shows the degree of dispersion of the yellow pigment used in Example 1. (The horizontal axis represents the particle diameter [nm], and the vertical axis represents the ratio [%] of particles having each particle diameter.)

FIG. 6 shows the degree of dispersion of the colorless fine particles used in Example 1. (The horizontal axis represents the particle diameter [nm], and the vertical axis represents the ratio [%] of particles having each particle diameter.)

FIG. 7 is a cross-sectional view schematically showing one example of a card with an image according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Thermal transfer recording medium 2 ... Support 3 ... Thermal transfer recording layer 4 ... Back coat layer 20 ... Card with image 21 ... Card support 22 ... Transparent layer 31 ..Cyan ink dots 32 ... Magenta ink dots 33 ... Yellow ink dots

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) B41M 5/40 B41M 5/26 HF term (reference) 2C005 HA01 HB02 HB10 JA01 JA08 JA18 JA19 JA26 JB02 JB06 JB07 JB14 JC02 KA06 KA15 LA11 LA20 LA30 LB08 MA01 MB01 MB08 QB03 TA21 TA22 2H111 AA26 AA47 AA48 AA52 BA33 BA38 BA53 BA61 BA74 BA78 CA03

Claims (21)

[Claims] 1. An image comprising at least an image formed by dots of a plurality of colors of ink on a support, and a transparent layer provided so as to cover the image. An image forming body comprising a high-molecular-weight organic polymer and colorless or pale-colored fine particles as main components, and the film thickness of the dots is in the range of 0.2 to 1.0 μm. 2. The image forming body according to claim 1, wherein the image forming body is a booklet-shaped passport, and the support is any one of a front cover, a back cover, and a bound page of the passport. An image forming body characterized in that: 3. An image forming body according to claim 1, wherein said image forming body is a seal-shaped or strip-shaped visa. 4. The image forming body according to claim 1, wherein the image forming body is a booklet, and the support is any one of a front cover, a back cover, and a bound page of the booklet port. Image forming body. 5. An image comprising at least an image formed by dots of a plurality of colors of ink on a support, and a transparent layer provided so as to cover the image. A card having a high quality organic polymer and colorless or light-colored fine particles as main components, and the film thickness of the dots is in the range of 0.2 to 1.0 μm. 6. The card with an image according to claim 5, wherein the plurality of color inks include at least three colors of yellow, magenta, and cyan. 7. The ink comprises 80% by weight of the color pigment.
The above is an organic pigment.
A card with an image according to any of the above. 8. The color pigment has an average particle diameter of 50 to 50.
The card with an image according to any one of claims 5 to 7, wherein the card is within a range of 0 nm. 9. The card with an image according to claim 5, wherein the colorless or light-colored fine particles have an average particle diameter in a range of 100 to 300 nm. 10. The ink, wherein the particle size distribution of the color pigment is such that the ratio of the color pigment having a particle size of more than 1 μm is 10%.
The image-attached card according to any one of claims 5 to 9, wherein: 11. The color pigment according to claim 5, wherein the width of the particle size distribution of the colorless or light-colored fine particles is narrower than that of the color pigment. Card with an image. 12. The compounding ratio of the color pigment, the amorphous organic polymer, and the colorless or light-colored fine particles in the thermal transfer recording layer is in the range of 20 to 60 parts by weight of the color pigment. The card with an image according to any one of claims 5 to 11, wherein the polymer is in a range of 40 to 80 parts by weight and the fine particles are in a range of 1 to 30 parts by weight. 13. An intermediate layer containing an amorphous organic polymer of the same kind as the amorphous organic polymer of the ink is provided on the support, and the image is formed by the intermediate layer and the transparent layer. The image-attached card according to any one of claims 5 to 12, wherein the card is arranged between the image card and the image card. 14. The amorphous organic polymer has a softening point of 70.
The card with an image according to any one of claims 5 to 13, wherein the card is an epoxy resin in a temperature range of -150 ° C. 15. The card with an image according to claim 5, wherein said card with an image is an IC card. 16. The card with an image according to claim 5, wherein said card with an image is a contactless card. 17. The card with an image according to claim 5, wherein said card with an image is a memory card. 18. The card with an image according to claim 5, wherein said card with an image is a hybrid card. 19. The card with an image according to claim 5, wherein said card with an image is a rewrite card. 20. The card with an image according to claim 5, wherein the card with an image is a magnetic recording card. 21. A second image formed by using at least one of a hologram, a diffraction grating, a fluorescent agent, and a magnetic material, and an image formed by dots of the plurality of colors of ink. 21. The support is formed so as to be visible on the same side surface.
A card with an image according to any of the above.