JP2015150870A - Intermediate transfer recording medium and image formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate transfer recording medium excellent in handleability of a print object, capable of forming a high-density image on a transfer object which is an optional object; and to provide an image formation method using the intermediate transfer recording medium.SOLUTION: An intermediate transfer recording medium 1 comprises at least a substrate 2, and a transfer part 10 provided peelably on one surface of the substrate 2, and the transfer part 10 is formed by laminating at least a peeling layer 3, an intermediate layer 4 and a reception layer 5 in this order from the substrate 2 side. The intermediate layer 4 contains at least inorganic fine particles.

Description

  The present invention relates to an intermediate transfer recording medium and an image forming method using the intermediate transfer recording medium.

  Conventionally, various thermal transfer recording methods are known. Among them, a thermal transfer sheet having a dye layer in which a dye for sublimation transfer is used as a recording material and this is supported on a base material such as a polyester film with a suitable binder. From the above, there are proposed methods for forming various full-color images by thermally transferring a sublimation dye onto a transfer material that can be dyed with a sublimation dye, for example, a thermal transfer image-receiving sheet having a dye-receiving layer formed on paper or a plastic film. Yes. In this case, as the heating means, the color dots having a large number of three or four colors adjusted by heating with the thermal head of the printer are transferred to the receiving layer of the thermal transfer image receiving sheet, and the multicolored color dots are transferred. To reproduce a full color image. The image formed in this way is very clear and excellent in transparency because the coloring material used is a dye, so the resulting image is excellent in the reproducibility and gradation of intermediate colors, It is possible to form a high-quality image similar to an image obtained by offset printing or gravure printing and comparable to a full-color photographic image.

  Such a thermal transfer image-receiving sheet is required to be used in various applications, and there is an increasing demand for forming a thermal transfer image on an object to be transferred which is an arbitrary object. As one of the countermeasures, an intermediate transfer recording medium in which a receiving layer is provided on a substrate so as to be peeled off, and a thermal transfer sheet having a dye layer on the receiving layer is used to transfer an dye to form an image. Thereafter, a method of heating the intermediate transfer recording medium and transferring the receiving layer onto the transfer target has been proposed and put into practical use.

  The thermal transfer image of a printed matter formed using this intermediate transfer recording medium has a problem of lack of durability such as weather resistance, friction resistance, chemical resistance and the like because the receiving layer on which the image is formed is located on the outermost surface. There is. Therefore, as shown in Patent Document 1, an intermediate transfer recording medium in which a release layer, a protective layer, and a receiving layer / adhesive layer are provided on a substrate has been proposed. According to this intermediate transfer recording medium, since the printed matter obtained has a protective layer formed on the surface of the thermal transfer image, durability can be imparted to the thermal transfer image.

  Further, in order to obtain a high-density and high-quality image of a printed material produced using an intermediate transfer recording medium, for example, Patent Document 2 discloses a porous layer which is a resin layer containing thermally foamable microcapsules. An intermediate transfer recording medium provided between a base material and a receiving layer has been proposed.

Prints produced using such an intermediate transfer recording medium are continuously discharged from the printer and stacked on the image receiving tray. The photographic paper discharged on the tray is not randomly stacked on the previously discharged photographic paper, but is stacked to some extent at random. For this reason, after printing a desired number of sheets, it is usually necessary to take out a bundle of printed materials from the tray and realign them neatly.
However, in the printed matter produced using the conventional intermediate transfer recording medium, the printed matter discharged from the printer is stuck to each other, and the continuously printed matter cannot be neatly arranged, that is, the printed matter cannot be judged. Often the problem (bad judgment) occurs.

JP 2004-351656 A JP-A-7-149070

  The present invention has been made in such a situation, and is an intermediate transfer recording medium that is excellent in the handling of printed matter and can form a high-density image on a transfer target, which is an arbitrary object, and the intermediate transfer recording medium It is a main object to provide an image forming method using an intermediate transfer recording medium.

  The above object is achieved by the present invention described below. That is, the present invention comprises at least a base material and a transfer portion that is detachably provided on one surface of the base material. The intermediate transfer recording medium is a laminated intermediate transfer recording medium, wherein the intermediate layer contains at least inorganic fine particles.

  The intermediate transfer recording medium is characterized in that the inorganic fine particles contained in the intermediate layer are at least one of alumina sol and colloidal silica.

  An image forming method using an intermediate transfer recording medium, wherein (1) at least a base material, at least a release layer on at least one surface of the base material, an intermediate layer containing at least inorganic fine particles, and a receiving layer are sequentially laminated. And a preparation step of preparing an intermediate transfer recording medium comprising a transfer portion provided in a peelable manner, and (2) an image forming step of forming an image on the receiving layer of the intermediate transfer recording medium by a thermal transfer method, (3 ) Transfer that transfers the receiving layer, the intermediate layer, and the release layer on which the image has been formed to the transfer body by superimposing and heating the receiving layer surface of the intermediate transfer recording medium on which the image has been formed on the transfer body. And (4) an image forming method comprising: discharging a sheet onto which the image-formed receiving layer, intermediate layer, and release layer have been transferred one sheet at a time to a sheet discharge portion. is there.

According to the intermediate transfer recording medium of the present invention, the obtained printed matter is excellent in discriminating properties, and it is possible to form a high-density image on a transfer target which is an arbitrary subject.
Further, according to the image forming method of the present invention, it is possible to easily form a high-concentration image on a transfer target, which is an arbitrary object, with excellent printability.

1 is a schematic cross-sectional view showing one embodiment of an intermediate transfer recording medium of the present invention. It is a schematic sectional drawing which shows other embodiment of the intermediate transfer recording medium of this invention. 1 is a schematic view showing an example of an image forming apparatus for explaining one embodiment of an image forming method using an intermediate transfer recording medium of the present invention.

Next, an embodiment of the invention will be described in detail.
FIG. 1 shows one embodiment of the intermediate transfer recording medium of the present invention. In the illustrated intermediate transfer recording medium 1, a release layer 3, an intermediate layer 4, and a receiving layer 5 are sequentially laminated on one surface of a substrate 2, and a heat resistant slipping layer 7 is provided on the other surface of the substrate 2. It is a configuration. In this case, the three layers of the release layer 3, the intermediate layer 4, and the receiving layer 5 are the transfer part 10 that can be peeled from the base material. Although FIG. 1 shows a form in which the heat-resistant slip layer 7 is provided on the other surface of the base material 2, the heat-resistant slip layer is not essential and can be omitted.

  FIG. 2 shows another embodiment of the intermediate transfer recording medium of the present invention. The illustrated intermediate transfer recording medium 1 has a release layer 3, an intermediate layer 4, a protective layer 6, a receiving layer on one surface of a substrate 2. The layers 5 are sequentially laminated, and the heat resistant slipping layer 7 is provided on the other surface of the substrate 2. In this case, the four layers of the release layer 3, the intermediate layer 4, the protective layer 6, and the receiving layer 5 are transfer portions 10 that can be peeled off from the substrate. In the intermediate transfer recording medium 1 shown in FIGS. 1 and 2, the intermediate layer 4 contains at least inorganic fine particles.

Hereinafter, each configuration of the intermediate transfer recording medium of the present invention will be described.
(Base material)
As the substrate 2 used in the intermediate transfer recording medium of the present invention, the same substrate as that used in the conventional intermediate transfer recording medium can be used as it is, and is not particularly limited. Specific examples of preferable substrates include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyphenylene sulfide, polyether ketone or polyether sulfone and other highly heat-resistant polyester, polypropylene, polycarbonate, cellulose acetate, polyethylene derivatives, poly Examples thereof include stretched or unstretched films of plastics such as vinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, polymethylpentene, and ionomer. Moreover, the composite film which laminated | stacked 2 or more types of these materials can also be used. Although the thickness of a base material can be suitably selected according to material so that the intensity | strength, heat resistance, etc. may become appropriate, the thing of about 1-100 micrometers is normally used normally.

(Heat resistant slipping layer)
The heat-resistant slip layer 7 can be provided for the main purpose of preventing thermal fusion between a heating device such as a thermal head and the substrate 2 and smooth running. In addition, it is considered that the intermediate layer described later in detail contains at least inorganic fine particles, which is considered to be a main factor for improving the spreading property of the printed matter. It is assumed that the printed matter will be improved in its handling.

  Examples of the resin used for the heat resistant slipping layer include cellulose resins such as ethyl cellulose, hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, and nitrocellulose, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, and polyvinyl. Vinyl resins such as acetal and polyvinyl pyrrolidone, acrylic resins such as polymethyl methacrylate, polyethyl acrylate, polyacrylamide, and acrylonitrile-styrene copolymers, polyamide resins, polyvinyl toluene resins, coumarone indene resins, polyester resins A simple substance or a mixture of natural or synthetic resins such as polyurethane resin, silicone-modified or fluorine-modified urethane is used. In order to further improve the heat resistance of the heat resistant slipping layer, among the above resins, a resin having a hydroxyl group reactive group is used, and a polyisocyanate or the like is used in combination as a crosslinking agent to form a crosslinked resin layer. It is preferable.

Further, in order to impart slidability with the thermal head, a solid or liquid release agent or lubricant may be added to the heat-resistant slip layer to provide heat-resistant slip. Examples of the release agent or lubricant include various waxes such as polyethylene wax and paraffin wax, higher aliphatic alcohols, organopolysiloxanes, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants. Activators, fluorosurfactants, organic carboxylic acids and derivatives thereof, fluororesins, silicone resins, fine particles of inorganic compounds such as talc, silica, and the like can be used. The amount of the release agent or lubricant contained in the heat resistant slipping layer is 5 to 50% by mass, preferably about 10 to 30% by mass. The thickness of such a heat-resistant slip layer, a conventionally known means, coating, drying, dry with 0.1 to 10 g / m ² approximately, preferably 0.5 to 5 g / m ² approximately be able to.

(Peeling layer)
The release layer 3 provided on the base material of the intermediate transfer recording medium of the present invention makes it easy to peel off the transfer part such as the receiving layer from the base material when transferring the receiving layer of the intermediate transfer recording medium to the transfer target, Furthermore, it has a protective layer function as the outermost surface layer of the transfer portion transferred to the transfer target. The release layer is generally composed of cellulose derivatives such as ethyl cellulose, nitrocellulose, and cellulose acetate, acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl acrylate, polyvinyl chloride, and vinyl chloride-vinyl acetate. It can be formed using a thermoplastic resin of a vinyl polymer such as a polymer or polyvinyl butyral, or a thermosetting resin such as an unsaturated polyester, polyurethane, or amino alkyd resin.

By including an ultraviolet absorber in the release layer, it is possible to improve the light resistance and weather resistance of the image of the transferred object that is covered with the intermediate layer after being transferred to the transferred object. Examples of the ultraviolet absorber to be used include salicylate-based, benzophenone-based, benzotriazole-based, substituted acrylonitrile-based, nickel chelate-based, hindered amine-based and the like, which are conventionally known organic ultraviolet absorbers. In addition, ultraviolet absorbers in which, for example, addition polymerizable double bonds such as vinyl groups, acryloyl groups, and methacryloyl groups, or alcoholic hydroxyl groups, amino groups, carboxyl groups, epoxy groups, and isocyanate groups are introduced into these ultraviolet absorbers. May be contained in the form of a functional resin. The release layer can be formed by known means such as gravure coating, gravure reverse coating, roll coating, etc., and the coating amount of the release layer is preferably about 0.5 to 5.0 g / m ^{2 in a} dry state.

(Middle layer)
On the base material of the intermediate transfer recording medium of the present invention, the intermediate layer 4 provided between the release layer and the receiving layer contains at least inorganic fine particles. Compared with other particles such as foamed particles, the inorganic fine particles are excellent not only in improving the dispersibility but also in ensuring transparency. In addition, since the inorganic fine particles give moderate heat insulation properties, this intermediate layer is assumed to be the main factor such as improving the spreading property of the obtained printed matter and increasing the image density of the printed matter. Is done.

  The inorganic fine particles used in the intermediate layer are preferably ultrafine particles of colloidal inorganic pigments, for example, metal silicates such as aluminum silicate and magnesium silicate; alumina or alumina hydrate (alumina sol, colloidal alumina, cationic) Conventionally known compounds such as metal oxides such as aluminum oxide or a hydrate thereof, pseudoboehmite, etc., silica or silica sol, magnesium oxide, titanium oxide, carbonates such as magnesium carbonate, and the like can be used. In the present invention, metal oxides and carbonates are preferred, metal oxides are more preferred, alumina or alumina hydrate is more preferred, and alumina sol is particularly preferred because of its high effect of imparting heat resistance and toughness. The intermediate layer may be composed of only one kind of the above-mentioned colloidal inorganic pigment ultrafine particles, or may be composed of two or more kinds of the above-mentioned colloidal inorganic pigment ultrafine particles.

The average particle size of the colloidal inorganic pigment ultrafine particles is usually 100 nm or less, preferably 50 nm or less, particularly preferably 3 to 30 nm. The average particle diameter can be obtained by a method of directly measuring the size of primary particles from an electron micrograph of a vertical cross section of the intermediate transfer recording medium according to the present invention. Specifically, the minor axis diameter and major axis diameter of each primary particle were measured, and the average was taken as the particle diameter of the particle. Next, for 100 or more particles, the volume (weight) of each particle was obtained by approximating the obtained particle size to a rectangular parallelepiped, and the volume average particle size was obtained and used as the average particle size. The same result can be obtained regardless of whether the electron microscope is a transmission type (TEM) or a scanning type (SEM).
The colloidal inorganic pigment ultrafine particles may be processed into an acidic type by adding a dispersion stabilizer such as hydrochloric acid or acetic acid for the purpose of facilitating dispersion in a sol form in an aqueous solvent. It may be one that has been subjected to surface treatment. The colloidal inorganic pigment ultrafine particles may be commercially available products such as alumina sol 100 (manufactured by Nissan Chemical Industries, Ltd.) and alumina sol 200 (manufactured by Nissan Chemical Industries, Ltd.).

  In the intermediate layer, in addition to the inorganic fine particle component, a resin component can be added. The resin component is, for example, a cellulose resin such as polyester resin, polyacrylate resin, polyurethane resin, styrene acrylate resin, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose butyrate, etc. And polyvinyl acetal resins such as polyvinyl acetoacetal and polyvinyl butyral, polyvinyl pyrrolidone resins, and polyvinyl alcohol resins. These resins may be used alone or in combination of two or more.

  It is preferable that the addition amount of said resin component is 0-50 mass% of the total solid of an intermediate | middle layer. When the intermediate layer is formed only from the inorganic fine particle component without the resin component in the intermediate layer, generally, an aqueous intermediate layer coating liquid composed of colloidal inorganic pigment ultrafine particles is applied onto the substrate and dried. Can be formed. The intermediate layer is more preferably formed by using a sol-gel method. Since the intermediate layer forms a film without using a binder resin, the intermediate transfer recording medium can have heat resistance and toughness, and the adhesiveness between the release layer and the receiving layer is good. In addition, the formation method of said sol-gel method performs drying by exposing to 90-130 degreeC hot air etc. in a coating so that it may become a dry gel form from the sol state of a colloidal inorganic pigment ultrafine particle. In this case, the intermediate layer coating solution can be prepared by dispersing colloidal inorganic pigment ultrafine particles in an aqueous medium.

The intermediate layer is formed by dispersing an inorganic fine particle in a solvent and, if necessary, dispersing or dissolving other resin components or the like in a solvent using a gravure coating method, a roll coating method, a screen It can be formed by coating and drying by a conventionally known forming means such as a printing method or a reverse roll coating method using a gravure plate. The intermediate layer can be applied in an amount such that the coating amount after drying is 0.01 to 5 g / m ² , but the coating amount after drying is high in terms of imparting excellent heat resistance, toughness and the like. it is preferred to coating in an amount of 0.05 g / m ² or more 1.0 g / m ² or less.

(Receptive layer)
The receiving layer 5 of the intermediate transfer recording medium in the present invention is for receiving the sublimation dye transferred from the thermal transfer sheet and maintaining the formed image. As the resin for forming the receiving layer, polycarbonate resin, polyester resin, polyamide resin, acrylic resin, cellulose resin, polysulfone resin, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-acetic acid Examples thereof include vinyl copolymer resins, polyvinyl acetal resins, polyvinyl butyral resins, polyurethane resins, polystyrene resins, polypropylene resins, polyethylene resins, ethylene-vinyl acetate copolymer resins, and epoxy resins.

  Further, a release agent can be contained in the receiving layer in order to improve the releasability from the thermal transfer sheet. Various release agents such as polyethylene wax, amide wax, solid waxes such as Teflon (registered trademark), fluorine or phosphate surfactants, silicone oils, reactive silicone oils, curable silicone oils, etc. Silicone oil, various silicone resins and the like can be mentioned, and silicone oil is preferable. An oily oil can be used as the silicone oil, but a curable oil may be used. Examples of the curable silicone oil include a reaction curable type, a photo curable type, and a catalyst curable type, and a reaction curable type and a catalyst curable type silicone oil are particularly preferable.

The addition amount of these silicone oils is preferably 0.5 to 30% by mass of the resin constituting the receiving layer. The release agent layer can also be provided by coating the release agent on a part of the surface of the receiving layer after dissolving or dispersing it in a suitable solvent and then drying. The thickness of the release agent layer, 0.01~5.0g / m ² in dry, especially 0.05 to 2.0 g / m ² is preferred. In addition, when silicone oil is added and formed when forming the receiving layer, silicone oil bleeds out on the surface after coating, but the release agent layer can be formed even if this is cured. In the formation of the receiving layer, pigments such as titanium oxide, zinc oxide, kaolin, clay, calcium carbonate, fine powder silica and the like are used for the purpose of improving the whiteness of the receiving layer and further enhancing the sharpness of the thermal transfer image. Fillers can be added. Moreover, you may add plasticizers, such as a phthalic acid ester compound, a sebacic acid ester compound, and a phosphoric acid ester compound.

Thermoplastic resins as described above and other necessary additives such as mold release agents, plasticizers, fillers, crosslinking agents, curing agents, catalysts, thermal mold release agents, ultraviolet absorbers, antioxidants, light stabilizers Or the like in a suitable organic solvent or dispersed in an organic solvent or water by, for example, a gravure printing method, a screen printing method, a reverse roll coating method using a gravure plate, etc. The receptor layer can be formed by coating and drying. The coating amount of the thus formed receptor layer is usually, 0.5 to 50 g / m ² approximately in the dry state, preferably 2 to 10 g / m ^2. Such a receiving layer is preferably a continuous coating, but may be formed as a discontinuous coating.

(Protective layer)
In the intermediate transfer recording medium of the present invention, the protective layer 6 can be provided between the intermediate layer provided on the substrate and the receiving layer. This protective layer is provided when the transfer layer such as the receiving layer of the intermediate transfer recording medium has been transferred to the transfer target and the protective layer function is insufficient with only the outermost release layer of the transfer portion. The protective layer is composed of at least a binder resin, and after being transferred to the transfer medium together with the receiving layer, a resin composition having desired physical properties is selected as the surface protective layer of the receiving layer.

  In general, cellulose derivatives such as ethyl cellulose, nitrocellulose, and cellulose acetate, acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl acrylate, polyvinyl chloride, vinyl chloride vinyl acetate copolymer, polyvinyl A thermosetting resin such as a vinyl polymer thermoplastic resin such as butyral, an unsaturated polyester resin, a polyurethane resin, or an aminoalkyd resin can be used as the protective layer resin. In the case where friction resistance, chemical resistance, and stain resistance are particularly required for the printed matter to which the receiving layer is transferred, an ionizing radiation curable resin can be used as the protective layer resin.

In addition, the protective layer uses a water-soluble resin emulsion such as polyvinyl alcohol, polyvinyl pyrrolidone, acrylic emulsion, urethane emulsion and the like, and further, crosslinked acrylic fine particles, crosslinked polystyrene fine particles, crosslinked polystyrene acrylic fine particles, and functional groups on the surface of these fine particles. Substantially transparent fine particles such as derivatives can be added to improve solvent resistance and plasticizer resistance. In addition, an ultraviolet absorber, an antioxidant and the like for improving the weather resistance can be added to the protective layer. The protective layer can be formed by the same method as the above receiving layer, and the coating amount is preferably 0.1 to 10 g / m ^{2 in a} dry state.

(Image forming method)
The image forming method of the present invention includes the following four steps.
(1) Intermediate transfer recording comprising at least a base material, and at least a release layer, an intermediate layer containing at least inorganic fine particles, and a receiving layer sequentially laminated on one surface of the base material, and a transfer portion provided so as to be peelable A preparation process for preparing the medium;
(2) an image forming step of forming an image on the receiving layer of the intermediate transfer recording medium by a thermal transfer method;
(3) The receiving layer, the intermediate layer, and the release layer on which the image is formed are transferred to the transferred body by heating the receiving layer surface of the intermediate transfer recording medium on which the image has been formed on the transferred body. A transfer process,
(4) It includes a discharging step of discharging the transfer target having the image-formed receiving layer, intermediate layer and release layer transferred one by one to a paper discharge section.

(First Step) A preparatory step for preparing an intermediate transfer recording medium, in which at least a release layer 3, an intermediate layer 4 containing at least inorganic fine particles and a receiving layer 5 are sequentially laminated on one surface of a substrate 2 and peeled In the preparation step of preparing the intermediate transfer recording medium 1 including the transfer section provided as possible, the intermediate transfer recording medium may be manufactured and prepared using the materials and manufacturing methods described above. An image forming apparatus for explaining one embodiment of the image forming method of the present invention will be described with reference to FIG. The intermediate transfer recording medium preparation step, which is the first step, is to wind the intermediate transfer recording medium winding 53 for supply after the production of the long intermediate transfer recording medium to a predetermined position of the image forming apparatus. Install.

(Second Step) An image forming step for forming an image by a thermal transfer system, and as shown in FIG. 3, a thermal transfer sheet provided with a dye layer and a colorant layer of a heat-meltable transfer layer on one surface of a substrate 20 is fed from the supply roll 51 and wound on the take-up roll 52, and the color is transferred from the color material layer of the thermal transfer sheet 20 to the receiving layer of the intermediate transfer recording medium 1 using the heating means of the thermal head 61. The material is transferred to form a thermal transfer image 70. The heating means is disposed between the thermal head 61 and the plantain roller 62 so that the receiving layer of the intermediate transfer recording medium 1 and the color material layer of the thermal transfer sheet 20 can be pressed against each other. By heating, the color dots whose heating amount is adjusted are transferred to the receiving layer, and a thermal transfer image 70 is formed. In this image forming process, since the intermediate transfer recording medium of the present invention described above is used, that is, since the intermediate layer has appropriate heat insulation and cushioning properties, the density of the thermal transfer image 70 is increased. Can be high.

(Third Step) This is a transfer step in which the receiving layer, intermediate layer and release layer on which the image 70 is formed are transferred from the intermediate transfer recording medium 1 on which the thermal transfer image 70 has been formed in the second step to the transfer target 30. In this transfer process, the intermediate transfer recording medium 1 passes through the heat roller 63, is guided by the guide roller, and is taken up by the take-up roll 54. Further, the transfer target 30 is fed one by one in the direction of the heat roller 63 from a state where a large number of sheets are stacked on a sheet feeding unit (not shown). Between the heat roller 63 and the transport roller 64, the receiving layer on which the thermal transfer image of the intermediate transfer recording medium 1 is formed and the transfer target 30 are disposed so as to be press-contactable. Then, the intermediate transfer recording medium 1 is heated from the substrate side by the heat roller 63 that is a heat source, whereby the thermal transfer image 70 is transferred to the transfer medium 30 together with the transfer portion of the release layer, the intermediate layer, and the receiving layer, and is printed. An object 40 is formed.

(Fourth Step) A discharge step of discharging the printed matter 40, on which the thermal transfer image 70 is transferred and formed on the transfer target 30 together with the transfer portion of the release layer, the intermediate layer, and the receiving layer in the third step, one by one to the discharge portion. It is. In this discharging step, after the transfer step of the third step, the printed matter 40 on which the thermal transfer image 70 is formed on the transfer target 30 and the intermediate transfer recording medium 1 are separated, and the intermediate transfer recording medium 1 is wound up. The printed matter 40 is wound around the roll 54 and conveyed one by one, and is deposited at the paper discharge unit. The printed matter of the paper discharge unit is not stacked at an accurate position on the previously discharged and transported printed matter, but is stacked randomly to some extent. For this reason, after printing the desired number of sheets, it is necessary to take out a bundle of printed materials from the paper discharge unit and realign them neatly. In the printed matter using the intermediate transfer recording medium used in the image forming method of the present invention, the continuously printed matter can be neatly arranged, that is, it has good handling properties, excellent workability, and is less likely to cause trouble. There are many advantages.

(Transfer material)
In the image forming method of the present invention, the transfer target 30 that can be used for transfer of the intermediate transfer recording medium is not particularly limited, and is, for example, natural fiber paper, coated paper, tracing paper, deformed by heat during transfer. Any plastic film, glass, metal, ceramics, wood, cloth, etc. may be used.

  Regarding the shape and application of the transferred object, stock certificates, securities, certificates, passbooks, boarding tickets, car horse tickets, stamps, stamps, appreciation tickets, admission tickets, tickets, etc., cash cards, credit cards, prepaid cards, Cards such as members cards, greeting cards, postcards, business cards, driver's licenses, IC cards, optical cards, cases such as cartons, containers, bags, forms, envelopes, tags, OHP sheets, slide films, bookmarks, Calendars, posters, brochures, menus, passports, POP supplies, coasters, displays, nameplates, keyboards, cosmetics, wristwatches, lighters and other accessories, stationery, report paper and other stationery, building materials, panels, emblems, keys, cloth, clothing , Footwear, radio, TV, calculator, OA equipment, etc., various samples , Album, In addition, computer graphics output, medical image output, etc., do not ask the kind.

Next, the present invention will be described more specifically with reference to examples and comparative examples. “Part” in the text is based on mass unless otherwise specified.
Example 1
A polyethylene terephthalate film having a thickness of 6 μm is used as the base material 2, and a coating solution for the release layer having the following composition is formed on one surface of the base material by a gravure coating method to 1.0 g / m ² after drying. The release layer 3 was formed by coating and drying. Next, on the release layer, the intermediate layer coating liquid 1 having the following composition is applied by drying so as to be 1.0 g / m ² after drying, and dried to form the intermediate layer 4. did.

<Coating liquid for release layer>
・ 95 parts acrylic resin (BR-87, manufactured by Mitsubishi Rayon Co., Ltd.)
-Polyester resin 5 parts (Byron 200, manufactured by Toyobo Co., Ltd.)
・ Toluene 200 parts ・ Methyl ethyl ketone 200 parts

<Intermediate layer coating solution 1>
・ Polyvinylpyrrolidone resin 3 parts (PVP K-90 made by IPS Japan Co., Ltd.)
Alumina sol (average primary particle size 10 nm × 100 nm, solid content 10%) 30 parts (alumina sol 200 manufactured by Nissan Chemical Industries, Ltd.)
・ Water 50 parts ・ IPA (isopropyl alcohol) 17 parts

On the intermediate layer 4, a receiving layer coating solution having the following composition is coated by gravure coating so as to be 2.0 g / m ² after drying, and dried to form a receiving layer 5. Then, an intermediate transfer recording medium 1 of Example 1 was produced.
<Coating liquid for forming receiving layer>
・ 95 parts of vinyl chloride-vinyl acetate copolymer (CNL, manufactured by Nissin Chemical Industry Co., Ltd.)
・ Epoxy-modified silicone oil 5 parts (KP-1800U, manufactured by Shin-Etsu Chemical Co., Ltd.)
・ Toluene 200 parts ・ MEK 200 parts

(Example 2)
An intermediate transfer recording medium was produced in the same manner as in Example 1 except that the intermediate layer coating liquid 1 in the intermediate transfer recording medium produced in Example 1 was replaced with the intermediate layer coating liquid 2 having the following composition.
<Intermediate layer coating solution 2>
・ Polyvinylpyrrolidone resin 3 parts (PVP K-90 made by IPS Japan Co., Ltd.)
・ Colloidal silica (average particle size 4-6 nm, solid content 10%) 30 parts ・ Water 50 parts ・ IPA (isopropyl alcohol) 17 parts

(Example 3)
An intermediate transfer recording medium was produced in the same manner as in Example 1 except that the intermediate layer coating liquid 1 in the intermediate transfer recording medium produced in Example 1 was replaced with an intermediate layer coating liquid 3 having the following composition.
<Intermediate layer coating solution 3>
-Urethane resin (solid content 35%) 10 parts (F-2850D, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
・ Alumina sol (average primary particle size 10 nm × 100 nm, solid content 10%) 15 parts (alumina sol 200 manufactured by Nissan Chemical Industries, Ltd.)
・ Water 37.5 parts ・ IPA (isopropyl alcohol) 37.5 parts

Example 4
An intermediate transfer recording medium was produced in the same manner as in Example 1 except that the intermediate layer coating liquid 1 in the intermediate transfer recording medium produced in Example 1 was replaced with an intermediate layer coating liquid 4 having the following composition.
<Intermediate layer coating solution 4>
・ Polyvinyl alcohol 3 parts (PVA-203 Kuraray Co., Ltd.)
・ Alumina sol (average primary particle size 10 nm × 100 nm, solid content 10%) 15 parts (alumina sol 200 manufactured by Nissan Chemical Industries, Ltd.)
・ Water 37.5 parts ・ IPA (isopropyl alcohol) 37.5 parts

(Example 5)
In the intermediate transfer recording medium produced in Example 1, a coating solution for a heat resistant slipping layer having the following composition was used on the other surface of the substrate, and the coating amount was 1 g / m ² when dried by the gravure coating method. Thus, the heat resistant slipping layer 7 was formed.
<Coating fluid for heat resistant slipping layer>
・ Polyvinyl acetal resin 90.3 parts (ESREC KS-1 manufactured by Sekisui Chemical Co., Ltd.)
・ 6.2 parts of polyisocyanate (Bernock D750, manufactured by DIC Corporation)
・ 0.62 parts of silicone resin filler (Tospearl 240 Momentive Performance Materials Japan GK)
-10 parts of zinc stearyl phosphate (LBT1830 purification, manufactured by Sakai Chemical Industry Co., Ltd.)
・ 10 parts of zinc stearate (SZ-PF manufactured by Sakai Chemical Industry Co., Ltd.)
・ 3 parts of polyethylene wax (Polywax 3000, manufactured by Toyo Adre Co., Ltd.)
・ Ethoxylated alcohol-modified wax 7 parts (Unitox 750, manufactured by Toyo Adre Co., Ltd.)
・ Methyl ethyl ketone 200 parts ・ Toluene 100 parts

(Comparative Example 1)
In the intermediate transfer recording medium produced in Example 1, the intermediate layer was deleted, and a release layer and a receiving layer were provided on the other side of the base material provided with the heat-resistant slip layer used in Example 1 on one side. Sequentially, the intermediate transfer recording medium was produced in the same manner as in Example 1.

(Comparative Example 2)
An intermediate transfer recording medium was produced in the same manner as in Example 1 except that the intermediate layer coating liquid 1 in the intermediate transfer recording medium produced in Example 1 was replaced with an intermediate layer coating liquid 5 having the following composition.
<Intermediate layer coating solution 5>
・ Polyvinylpyrrolidone resin 3 parts (PVP K-90 made by IPS Japan Co., Ltd.)
・ Water 72.5 parts ・ IPA (isopropyl alcohol) 22.5 parts

(Comparative Example 3)
The intermediate layer coating liquid 1 in the intermediate transfer recording medium produced in Example 1 is replaced with the intermediate layer coating liquid 6 having the following composition, and dried to 15.0 g / m ² and dried. Thus, an intermediate transfer recording medium was produced in the same manner as in Example 1 except that the intermediate layer 4 was formed.
<Intermediate layer coating solution 6>
-Polyester resin (Toyobo Co., Ltd., Byron 600) 100 parts-Foamable microcapsules (foamed with an average particle size of 15 μm, Matsumoto Yushi Seiyaku Co., Ltd., F-80) 10 parts-Ethyl acetate 200 parts-IPA (Isopropyl alcohol) 200 parts

  Yellow obtained by color-separating a face photograph with an HID HDP-5000 printer using the intermediate transfer recording media of Examples 1 to 5 and Comparative Examples 1 to 3 and a thermal transfer sheet for an HID printer HDP-5000. According to each image information of magenta and cyan, yellow, magenta and cyan dyes are transferred to the receiving layer of the intermediate transfer recording medium, so that a full-color face photographic image is further transferred to the receiving layer of the intermediate transfer recording medium, and further yellow, A magenta and cyan three-color grayscale image was formed.

  In the HID printer HDP-5000, the receiving layer of the intermediate transfer recording medium on which the thermal transfer image is formed and the card substrate made of white vinyl chloride resin shown in the following conditions are in contact with each other. A printed material in which a transfer portion including a receiving layer having a thermal transfer image on the material was transferred was prepared.

(Material composition of card substrate)
-Polyvinyl chloride compound (degree of polymerization 800) 100 parts (contains about 10% of additives such as stabilizers)
・ White pigment (titanium oxide) 10 parts ・ Plasticizer (DOP) 0.5 parts

The print density comprising the obtained Examples and Comparative Examples was evaluated under the following conditions.
(Print density)
The maximum density of the gray scale of the thermal transfer image on the card which is each of the obtained prints was examined. The printing density of the image was measured by an optical densitometer (manufactured by Gretag Macbeth; spectrolino). Evaluation was made according to the following criteria.
○: The highest density is 1.8 or more, and the transfer sensitivity is high.
X: The maximum density is less than 1.8, and the transfer sensitivity is low.

(Judgment)
As shown in FIG. 3, each printed material produced under the above conditions was discharged 10 by 10 in each example in a discharging process of discharging the printed materials one by one to the paper discharging unit, and 10 sheets were stacked and accumulated. . The ease with which the deposited prints were arranged (separability) was evaluated according to the following criteria.
◯: Can be easily aligned and has good judgment.
X: Cannot be easily aligned, and the judgment property was poor.

Table 1 below shows the evaluation results of the print density and the spreadability of the above printed matter.

As shown in the above results, according to the intermediate transfer recording media of Examples 1 to 5, good results were obtained in all of the evaluations of the print density and the spreading property of the printed matter.
According to the intermediate transfer recording media of Comparative Examples 1 to 3, the print density and the evaluation of the printed matter were all poor. However, in the case of the intermediate transfer recording medium of Comparative Example 3, the print density was lowered due to the conspicuous unevenness of the image surface of the printed material, resulting in poor image quality.

DESCRIPTION OF SYMBOLS 1 Intermediate transfer recording medium 2 Base material 3 Peeling layer 4 Intermediate layer 5 Receiving layer 6 Protective layer 7 Heat resistant slipping layer 10 Transfer part

Claims (3)

  An intermediate transfer comprising at least a base material and a transfer portion provided on one surface of the base material so as to be peelable. The transfer portion is laminated from the base material side in the order of at least a release layer, an intermediate layer, and a receiving layer. An intermediate transfer recording medium, wherein the intermediate layer contains at least inorganic fine particles.   2. The intermediate transfer recording medium according to claim 1, wherein the inorganic fine particles contained in the intermediate layer are at least one of alumina sol and colloidal silica. An image forming method using an intermediate transfer recording medium,
(1) Intermediate transfer recording comprising at least a base material, and at least a release layer, an intermediate layer containing at least inorganic fine particles, and a receiving layer sequentially laminated on one surface of the base material, and a transfer portion provided so as to be peelable A preparation process for preparing the medium;
(2) an image forming step of forming an image on the receiving layer of the intermediate transfer recording medium by a thermal transfer method;
(3) The receiving layer, the intermediate layer, and the release layer on which the image is formed are transferred to the transferred body by heating the receiving layer surface of the intermediate transfer recording medium on which the image has been formed on the transferred body. A transfer process,
(4) An image forming method characterized by comprising a discharging step of discharging the transferred material onto which the receiving layer, the intermediate layer, and the release layer on which the image has been formed, to the paper discharge unit one by one.

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