JPH0447634B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a dye transfer body used for recording by thermal transfer, and in particular a transfer body for thermal recording (hereinafter simply referred to as a transfer body) used for high-speed recording using electronic devices such as a thermal head or a laser beam. Regarding. Structure of conventional example and its problems As shown in FIG. 8, the conventional transfer body has a base 11
A color material layer 12 with a smooth surface made of a sublimable dye and a binder was provided on one side of the . However, with this configuration, there is a problem of disturbance in image quality in the intermediate tone area. The main causes of this are drop-outs in the recording in areas where energy is applied and sublimation or scattering of the sublimable dye (noise) in areas where energy is not applied. In addition, when a thermal head is used as a recording means, a transfer body using an inexpensive and homogeneous film used to obtain a uniform image is fused by the high temperature generated by the thermal head, and is stable on the thermal head. I was unable to drive. OBJECTS OF THE INVENTION It is an object of the present invention to provide a transfer member that reduces dropouts and noises, particularly in the intermediate tone area, and that provides good recording image quality by running stably on a thermal head. Structure of the Invention In order to achieve the above object, the transfer body of the present invention is provided with a lubricating heat-resistant layer made of fine particles, a liquid lubricating substance, and a polymeric substance on one side of a substrate, and a sublimation-resistant layer on the other side. A coloring material layer consisting of a dye, non-sublimable particles, and a binder is provided, and a portion of the non-sublimable particles protrude from the surface of the coloring material layer. Effects According to the above structure, the heat resistance of the lubricating heat-resistant layer in contact with the thermal recording means such as the thermal head is improved by the heat-resistant resin, the surface is roughened by the fine particles, and the liquid lubricant substance is smoothed by the heat-resistant resin. Since a small amount of the heat-resistant layer flows out from inside the heat-resistant layer, stable running properties of the transfer body can be imparted. Furthermore, due to the presence of non-sublimable particles in the coloring material layer that serve as a spacer, the transfer member and the image receiver are not subjected to any more pressing force than necessary. DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. The transfer body 1 shown in FIG. 1 is composed of a slippery heat-resistant layer 3 formed on one side of a base film 2 and a coloring material layer 4 formed on the other side. It consists of a binder and non-sublimable particles 5, and some of the non-sublimable particles 5 partially protrude from the surface l of the coloring material layer 4. As shown in FIG. 2, the proportion of the non-sublimable particles 5 is within a range 4a surrounded by a circle with radius r=200 μm from each point of the cross section 5a of the non-sublimable particles 5 on the surface l of the coloring material layer. The effect is great when the points are occupied by other non-sublimable particles. Among these, it has a particularly significant effect when other non-sublimable particles are present somewhere in the area surrounded by a circle with a radius of 20 μm. Furthermore, as shown in FIG. 1, non-sublimable particles 5
The height h from the surface l of the coloring material layer 4 is 0.1 to 100 μm
Good results are shown if the value is within the range of 1μm≦
It has an especially excellent effect when h≦10μm.
That is, the appropriate particle size of particles 5 is 0.1 to 100 μm,
In particular, it is 1 to 10 μm. In the present invention, the non-sublimable particles 5 do not necessarily need to be exposed beyond the coloring material layer 4;
As shown by the broken line in the figure, the non-sublimable particles 5 may be covered with a sublimable dye layer 4'. In this case, the surface l will be as shown in the figure. Even in this case, the effect of the non-sublimable particles described later is not impaired at all. Furthermore, the non-sublimable particles 5 having the shape shown in FIG. 4 are distinguished by broken lines in the figure and are regarded as two particles. The same applies to those having three or more protrusions. The effect of non-sublimable particles remains the same not only when they are present on the substrate, but also when they are partially embedded within the substrate. Next, to explain the effect of the non-sublimable particles 5 using a recording example shown in FIG. 5 using a thermal head, the coloring material layer 4
When the image receptor 6 and the image receptor 6 are opposed to each other and heated by the thermal head 7 disposed on the side of the slippery heat-resistant layer 3, the non-sublimable particles 5 prevent the colorant layer 4 and the image receptor 6 from coming into direct contact. Therefore, the sublimable dye does not migrate due to pressing or melting, and the sublimable dye migrates only by sublimation or vaporization, giving a good transparent image. Furthermore, the binder has the following effects. That is, since a sufficient amount of sublimable dye is retained and the distance between the surface l of the coloring material layer and the image receptor 6 is brought close, sufficient recording density is given to the image, and the transfer body is made to withstand repeated use. obtain. Note that r = 200 μm indicated by the diagonal line outside of Figure 2.
If there are no other non-sublimable particles within the range of , or if h in FIG. 1 is smaller than 0.1 μm, the effect of the non-sublimable particles is not sufficient. , h exceeds 100 μm, sublimation of the sublimable dye is hindered, and an image with sufficient recording density cannot be obtained. Here, h is the maximum height of the non-sublimable particles 5 measured from the surface l of the coloring material layer. Needless to say, the density of the non-sublimable particles 5 on the transfer body to obtain good halftone image quality depends on the size of the pixel, the smoothness and homogeneity of the substrate and image receptor, etc. As the smoothness and homogeneity of the substrate, image receptor, etc. increases, the non-sublimable particles function as spacers at a lower density. The density of the non-sublimable particles 5 is reflected in the dpi value described in the example in FIG. Regarding the shape of the non-sublimable particles 5, spherical particles are particularly effective. This is because the individual spherical particles have exactly the same spacer function no matter how they are positioned relative to the transfer body. That is, as shown in FIG.
The distance between the image receptor 6 and the image receptor 6 does not change at all. Among the non-sublimable particles 5, metals, metal oxides, polymer compositions, etc. are particularly effective due to their large rigidity or elasticity. In the transfer body of the present invention, dyes used include disperse dyes, basic dyes, and diformers of basic dyes. In addition, binders with high melting points or softening properties such as polysulfon, polycarbonate, polyphenylene oxide, and cellulose derivatives do not cause melting and transfer to the image receptor due to heat during recording, and can produce high-quality transparent images. Contribute to obtaining. Note that even when multiple types of sublimable dyes are used, very unique effects are exhibited. That is, in order to obtain a black image with sublimable dye, it is customary to
Multiple types of sublimable dyes are used. However,
Due to non-uniform transfer of sublimable dyes due to direct contact between the coloring material layer and image receptor, and preferential transfer of sublimable dyes near the image receptor, it is possible to apply a wide range of recording densities from low to high recording densities. It was extremely difficult to obtain a good black image over the entire area. However, in a transfer body constructed using these particles together with non-sublimable particles, the transfer to the image receptor is facilitated by uniform sublimation of each sublimable dye, and the preferential transfer of the sublimable dye existing near the image receptor is facilitated. Since there is no heavy transfer, each sublimable dye is evenly transferred to the image receptor, resulting in good black images over a wide recording density range. If at least one of the multiple types of sublimable dyes is selected from basic dyes (including colored dyes or color formers that develop color with electron acceptors) and at least one type is selected from disperse dyes, the image receptor By appropriate selection of , black with extremely good color tone and high recording density can be obtained. This is thought to be because the basic dye and the disperse dye have different die sites (adhesion points) and do not cause harmful interactions with each other in dyeing and color development. Also,
In addition to these, by combining suitable types of sublimable dyes, good images of arbitrary hues can be obtained in a wide range of recording densities. Further, excellent effects are obtained when the volume ratio of non-sublimable particles to the binder is within the range of 10 ^-3 to 10 ² . At lower ratios, the effect of non-sublimable particles is not significant, and at higher ratios they are not sufficiently bound by the binder. Among these, a ratio of 10 ^-2 to 10 is most effective. In addition, in order to fully demonstrate the function of a spacer, it is necessary that at least 3 non-sublimable particles exist per transfer substrate corresponding to each pixel, and if they are present at less than this density, it will not work as a spacer. The function is insufficient and noise appears in the image. A more specific example will be described. A polyethylene terephthalate film with a thickness of 9 μm is used as the substrate 2. There is a first mark on the underside of this film.
A coating solution having the composition shown in the table was applied with a wire bar, the solvent was evaporated with hot air at 60°C, and the coating was cured by irradiation with a 1KW high-pressure mercury lamp to obtain a slippery heat-resistant layer 3.

[Table] In Table 1, silicone oil is a liquid lubricating substance and epoxy acrylate resin is a polymeric substance. Next, 5 parts by volume of a sublimable dye represented by the structural color below, 5 parts by volume of polycarbonate, and dichloromethane.
100 parts by volume and average particle size 3μm as non-sublimable particles
Alumina particles were mixed in varying amounts and stirred separately in a ball mill, and the dispersion liquid was coated on the upper surface of the above substrate with a wire bar to obtain a transfer body. Using these, images were drawn on activated clay paper using a thermal head. The recording conditions were as follows. Main scanning and sub-scanning linear density: 4 dots/mm Recording power: 0.7 W/dot Thermal head heating time: 4 msec Table 2 shows the number of dropouts and noise per 1000 dots, and the amount of alumina present in the transfer material. Length max of the minimum distance dpi between the projected figures between particle pi and particles existing in its vicinity
(dpi). Figure 6 shows the relationship between particle arrangement and dpi. The dpi was determined from scanning electron micrographs taken perpendicularly to capacitor paper. Further, h as defined in FIG. 1 was determined from scanning electron micrographs of the cross section of the transfer body, and was 7 μm or less in all cases where the amount of alumina particles was varied. In addition, as a comparative example, the results when no alumina is mixed are also shown.

[Table] From the above results, according to this example, an image can be imaged using a transfer body in which the coloring material layer contains alumina particles (non-sublimable particles) in which some particles protrude from the surface of the coloring material layer. This reduces dropouts and noise, and since a smooth heat-resistant layer is provided on one side of the transfer body, it can run stably. Note that the scope of the present invention is not limited to the examples, and similar effects were obtained in various embodiments as described below. The materials that make up the non-sublimable particles include metals, metal oxides, metal sulfides, metal carbides, graphite, carbon black, silicon carbide, minerals, inorganic salts,
Selected from organic pigments and polymeric compositions. Examples of highly effective methods are listed below. Metal: aluminum, silicon, germanium,
tin, copper, zinc, silver, iron, cobalt, nickel,
Chromium and alloys based on chromium. Metal oxides: alumina, beryllium oxide, magnesium oxide, cuprous oxide, zinc oxide, indium oxide, tin oxide, titanium oxide, silicon oxide, iron oxide, cobalt oxide, nickel oxide, manganese oxide, tantalum oxide, vanadium oxide, oxide Tungsten, molybdenum oxide, and their compounds doped with impurities. Metal sulfides: copper sulfide, zinc sulfide, tin sulfide, molybdenum sulfide. Minerals: Magnesium minerals, coal minerals, strontium minerals, barium minerals, zirconium minerals, titanium minerals, tin minerals, phosphorus minerals, aluminum minerals (waxite, kaolin, clay), silicon minerals (quartz, mica, talc, zeolite, diatom) soil). Inorganic salts: Carbonates or sulfates of alkaline earth metal elements (magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium sulfate, calcium sulfate, strontium sulfate, barium sulfate) and metal silicates. Polymer compositions: phenolic resin, melamine resin, urethane resin, epoxy resin, silicone resin, urea resin, diallyl phthalate resin, alkyd resin, acetal resin, acrylic resin, methacrylic resin, polyester resin, cellulose resin, starch and its derivatives , polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene,
Fluororesin, polyethylene, polypropylene, polystyrene, polydivinylberzene, polyvinyl acetal, polyamide, polyvinyl alcohol, polycarbonate, polysulfone, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyether ether ketone, polyamino bismaleimide, Polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyimide, polyamideimide, polyacrylonitrile, AS resin, ABC resin, SBR, and compositions based on these. All of these materials have high mechanical strength and will not be destroyed by the pressure of bringing the transfer member and receiver into close contact, for example, and are suitable for achieving the objectives of the present invention. In addition to the above-mentioned polymer compositions, those having a melting point or softening point of 100° C. or higher are particularly effective. This is because many of the sublimable dyes used have sufficient sublimation ability even below 100°C.
This is because a polymer composition that satisfies this condition is not transferred to the image receptor, so that a high-quality transparent image can be obtained using only the sublimable dye. The substrate of the transfer body of the present invention is not particularly limited, but a polymer film is particularly useful. For example, ester polymers such as polyethylene terephthalate, polyethylene naphthalate, and polycarbonate, amide polymers such as nylon,
Cellulose derivatives such as acetyl cellulose and cellophane, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, fluorine polymers such as tetrafluoroethylene, ether polymers such as polyoxymethylene and polyacetal, polystyrene, Olefin polymers such as polyethylene, polypropylene, and methylpentene polymers, imide polymers such as polyimide, polyamideimide, and polyetherimide can be used. In particular, polyester-based polymers are useful because they are thin, have a certain degree of heat resistance, and are inexpensive. In addition, imide-based, amide-based, and other polymers whose substrates are more heat-resistant than polyester-based polymers are useful when the transfer body is used repeatedly or at high speeds because they have excellent heat resistance. The polymer material used for the slippery heat-resistant layer is not particularly limited, and may include thermoplastic resin, heat,
Various resins (crosslinked resins) cured by light, electron beam, etc. can be used. In particular, the cured resin has good adhesion to the substrate and good heat resistance. Examples include silicone-based, acrylate-based, epoxy-based, and unsaturated aldehyde-based resins. Among these, cured products of acrylate resins exhibit excellent properties. Furthermore, since the resin cured by light or electron beams is easily cured in a short time, it is easy to produce a long transfer body and exhibits good characteristics.
For example, oligoacrylates, spirane resins cured with light or electron beams, or epoxy resins photocured with an aromatic diazonium salt catalyst are excellent. Various reactive diluents can be added to the resin. The thickness of the slippery heat-resistant layer is not particularly limited. Generally 0.1μm from the manufacturing point of view
Films with a thickness greater than 100% are easy to obtain and exhibit uniform properties. The fine particles contained in the slippery heat-resistant layer include metals,
Metal oxides, metal sulfides, metal carbides, graphite, carbon black, minerals, inorganic salts, organic salts, organic pigments, etc. can be used, but synthetic amorphous silica, carbon black, alumina, titanium oxide, etc. are particularly effective. be. Synthetic amorphous silica includes anhydrous silica and hydrated silica, and ultrafine particles produced by a gas phase method are useful as anhydrous silica. for example,
High-purity ultrafine particulate silica (trade name: Aerosil, manufactured by Nippon Aerosil Co., Ltd.) developed by West German Degussa, aluminum oxide and titanium oxide (both manufactured by Nippon Aerosil Co., Ltd.) similarly produced by the gas phase method. ) etc. Depending on the characteristics of the sublimable dye used, ultrafine silica may react with the sublimable dye, so in such cases, the silanol groups present in the silica may be partially replaced with methyl groups, etc. Bound hydrophobic silica can be used. Ultrafine particles are well dispersed by ultrasonic waves, triple rolls, homogenizers, and the like. White carbon is mainly composed of hydrated silicon dioxide and may also contain calcium silicate. For example, "Carplex" manufactured by Shionogi & Co., Ltd.
It is commercially available under names such as "Nipseal" manufactured by Nippon Silica Kogyo Co., Ltd. and "Silton" manufactured by Mizusawa Chemical Industry Co., Ltd. The fine particles can be used in an amount of 0.1 to 20.0% by weight based on the binder of the polymer composition. Particularly stable characteristics are exhibited when the addition ratio is in the range of 5 to 10.0% by weight. Examples of liquid lubricating substances include dimethylpolysiloxane, methylphenylpolysiloxane,
Methylhydrodiene polysiloxane, fluorosilicone oil, and various other modified silicone oils (epoxy-modified, alkyl-modified, amino-modified, carboxyl-modified, alcohol-modified, polyether-modified, alkyl, aralkyl, polyether-modified,
epoxy, polyether modified, etc.), silicone-based lubricating substances such as copolymers of silicone and organic compounds such as polyoxyalkylene glycol, various fluorine-based surfactants such as fluoroalkyl compounds,
Fluorinated lubricating substances such as low polymers of trifluorochloroethylene, synthetic oils such as alkylbenzenes, polybutenes, alkylnaphthalenes, alkyl diphenylethanes, phosphoric acid esters, polyalkylene glycol oils, saturated hydrocarbons, animal and vegetable oils, There is mineral oil. Effects of the Invention As described above, the heat-sensitive recording transfer member of the present invention provides recorded images with stable transfer runnability and good image quality with reduced dropouts and noise. Furthermore, full-color images can be obtained using three types of dye transfer bodies that develop cyan, magenta, and yellow colors.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a transfer body for thermal recording in one embodiment of the present invention, FIG. 2 is a sectional view of a part of the same transfer body, and FIG. 3 is a longitudinal sectional view of a transfer body in another embodiment. , FIG. 4 is a vertical cross-sectional view of a transfer body in another embodiment, FIG. 5 is a vertical cross-sectional view showing how the transfer body is used, and FIG. 6 is a diagram showing the distribution of non-sublimable particles in the transfer body. , FIG. 7 is a longitudinal sectional view showing another state of use of the transfer body, and FIG. 8 is a sectional view of the conventional transfer body. 1... Transfer body for thermal recording, 2... Substrate, 3...
Smooth heat-resistant layer, 4...coloring material layer, 5...non-sublimable particles.

Claims (1)

[Scope of Claims] 1. A slippery heat-resistant layer made of fine particles, a liquid lubricating substance, and a polymeric substance is provided on one surface of a substrate, and a sublimable dye, non-sublimable particles, and a binder are provided on the other surface. 1. A transfer body for heat-sensitive recording, characterized in that a coloring material layer is provided, and a portion of the non-sublimable particles protrudes from the surface of the coloring material layer. 2. Claims in which any point within the range surrounded by a circle with a radius of 200 μm from each point on the outer periphery of the cross section of any non-sublimable particle on the surface of the coloring material layer is occupied by other non-sublimable particles The transfer body for thermal recording according to item 1. 3. The heat-sensitive recording transfer member according to claim 1 or 2, wherein the height of the protruding non-sublimable particles from the surface of the coloring material layer is within the range of 0.1 to 100 μm. 4. The transfer body for thermal recording according to claim 1 or 2, wherein the non-sublimable particles have a particle size in the range of 0.1 to 100 μm. 5. The thermal recording transfer body according to claim 1 or 2, which has three or more non-sublimable particles in any part corresponding to a pixel. 6. The heat-sensitive recording transfer body according to claim 1 or 2, wherein the average particle size of the fine particles in the slippery heat-resistant layer is 6 μm or less.