JP3452031B2 - ink ribbon - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon suitable for use in, for example, an ink ribbon for a color video printer by a thermal transfer system. [0002] For example, in order to print out an image photographed by an electronic still camera or the like on a photographic paper in the same manner as a silver halide photograph, an image formation by a thermal transfer method has been attempted. In this thermal transfer method, an ink ribbon containing a dye is brought into contact with photographic paper on which a receiving layer is formed,
The ink ribbon is heated by a thermal head or the like to transfer the dye of the ink ribbon to the receiving layer of the photographic paper. Polyester or the like is used for the receiving layer of the photographic paper, and a disperse dye or the like is used for the dye of the ink ribbon. [0003] By the way, the disperse dyes usually used in this type of system have been devised variously as disclosed in Japanese Patent Application Laid-Open Nos. 1-259989 and 1-275096. After the transfer to the receiving layer, however, the polymer is merely held in the receiving layer by interacting with the polymer of the receiving layer, such as van der Waals force, dipole force, hydrogen bonding, and the like. Therefore, when an image is formed, if it comes into contact with a resin or a solvent that has a higher affinity for the dye, or if heat energy sufficient to cancel these interactions is supplied, transfer or elution of the dye is induced, Inconveniences such as blurring occur. Under such circumstances, for example, Japanese Patent Application Laid-Open No.
78893, JP-A-60-2398, JP-A-60-110494, JP-A-60-220078
No. 5, JP-A-60-260381, JP-A-6-260381
As disclosed in Japanese Patent Application No. 0-260391, a means based on the formation of a chemical bond has been proposed. The methods disclosed therein are methods in which a compound having a corresponding group is contained in a receptor layer using a dye having a group capable of reacting with an epoxy group or an isocyanate group, and a dye having an acryloyl group or a methacryloyl group. And a method in which a compound having active hydrogen is contained in the receiving layer using a dye. Further, a method in which a metal compound is contained in the receiving layer using a dye capable of forming a metal complex, and a low-molecular compound having an active methyl group (or methylene group) There is a method of forming a dye by sublimating a compound and reacting it with an aldehyde (nitroso) compound in a receptor layer. [0006] However, in the means based on the formation of chemical bonds, the reactivity of the dye or the receiving layer is high and the storage stability is poor, and the reaction is not completed in a short time and a stable image is obtained. There are drawbacks such as that it takes a long time to form, that the preparation of the dye is difficult and the types of dyes that can be used are limited,
Further, even with these means, it is difficult to say that the fixing property is sufficient. As described above, in the conventional thermal transfer system,
In particular, transfer of the dye due to lack of fixing property is a great hindrance to practical use, and improvement thereof is desired. Accordingly, the present invention has been proposed in view of such conventional circumstances, and has as its object to provide an ink ribbon having excellent thermal transfer sensitivity and capable of imparting fixing properties comparable to silver halide photographic images. And In the present invention, the fixing type heat-sensitive transfer type image forming material disclosed in Japanese Patent Application No. 3-89592 is completely hydrophobic (low dielectric constant medium system), while the fixing effect by salt formation is obtained, whereas hydrophilicity is obtained. It is an object of the present invention to obtain a similar salt-forming fixing action even in a system (high dielectric constant system). [0009] The ink ribbon of the present invention.
Is an ink ribbon for the dye transfer type thermal transfer system.
And the inorganic ion of the acid dye has an appropriate hydrophilicity
Acid dyes having amphiphilic properties substituted by cations
An ink layer 1 is formed on a support 2, and organic cations for amphipathizing an acidic dye are tetra-n-hexylammonium bromide, tetra-n-butylammonium borofluoride, tetra-n-perchlorate. Butylammonium, cetyltrimethylammonium bromide, dioctadecyldimethylammonium chloride, myristyldimethylbenzylammonium chloride, benzyldimethylchloride
[2- [2- (P-1,1,3,3-tetramethylbutyl) ethoxy] ethyl] ammonium, alkyl pyridinium salts, is at least 1 Tanedea Louis Nkuribon selected from imidazolinium salts . According to the present invention, with respect to photographic paper laking by salt formation of the acid dye charge contains a precipitant capable, contacted the ink ribbon containing an acidic dye charges having amphiphilic, thermal stimulation by by an acidic dye fees <br/> migrated fixing the photographic paper from the ink ribbon, in particular a fixing property can be dramatically improved, image fixability comparable to silver salt photographic images has been granted Can be obtained. Hereinafter, embodiments of the ink ribbon of the present invention will be described. First, a method for manufacturing the ink ribbon of the present invention will be described with reference to FIG. Preparation of Dyes Acid Dye System An aqueous solution of 1000 g of 10 g of sodium copper phthalocyanine tetrasulfonate (manufactured by Kodak Co., Ltd.) was prepared, and 19.57 g of tetra-n-hexyl bromide was added to this solution. Water-ethanol (1/1) that dissolves ammonium
(Volume ratio) The solution was dropped into 2000 cc. An aliquot of chloroform was added to a portion of the mixed solution, shaken with an equal amount of chloroform, and allowed to stand. When the mixture was allowed to stand, the dye was distributed to the oil phase at a distribution ratio of about 0.3 (Oil / Water). A similar extraction experiment revealed that the starting material hardly partitioned into the oil phase and was amphiphilized by the treatment described above. Next, when a large amount of water was added to the mixed solution, a dark blue precipitate was deposited. The precipitate was collected by filtration, washed with hexane, and dried at room temperature under reduced pressure to obtain about 30 g of a solid. Although the starting dye was insoluble in ethanol, this operation made it soluble in a mixed solvent of water and ethanol. In order to purify the dye, about 30 g of the dye was dissolved in 200 g of a water-ethanol mixed solution, and 2 g of acid clay was added thereto.
After stirring with ultrasonic waves for one minute, the precipitate was separated by filtration and the filtrate was dried under reduced pressure using an evaporator to obtain a dye in substantially the same amount as the starting material. Basic Dye System (Reference Example) Next, the dyes of the three primary colors (mixed color reduction) of yellow (Y), magenta (M) and cyan (C) were amphiphilicized. Auramine O (Y), rhodamine B (M) and methylene blue (C) hydrochloride were used as the dye matrix. First, 600 cc of an aqueous solution in which 2 g of auramine O (Y) is dissolved is prepared, and an ethanol solution containing 1 g of sodium paratoluenesulfonate is prepared.
When 0 g was dropped, a precipitate was deposited. The precipitate was collected by filtration, washed with hexane, and dried at room temperature under reduced pressure to obtain about 2 g of a solid. Although the starting dye was insoluble in MEK, this operation made it soluble in the water-MEK mixed solvent and clearly showed amphiphilicity. Rhodamine B (M) and methylene blue (C) were amphiphilized in exactly the same manner as above. Preparation of Ink Ribbon Acid Dye System An ink ribbon was prepared using the acid dye shown in the above embodiment. The obtained phthalocyanine dye was dissolved in MEK with the following composition together with a polyester resin as a binder polymer to form a coating solution. Composition parts by weight Polyester 1 Dye 1 MEK 20 This solution was applied to a PET film having a heat-resistant lubricating layer on the back side using a wire bar, and then 12
The ribbon was dried with hot air at 0 ° C. for 2 minutes to obtain a ribbon having a transparent colored layer having a thickness of about 1 μm when dried. Basic Dye System (Reference Example) The basic dye obtained in the above example was dissolved in a MEK / ethanol mixed solution in which polyvinyl butyral (trade name BL-1; manufactured by Sekisui Chemical) was dissolved. (Three types) were obtained. Composition parts by weight Polyvinyl butyral 1 Dye 1 MEK / ethanol (1/1 wt ratio) 50 This solution was applied to a PET film having a heat-resistant lubricating layer on the back side using a wire bar, and then 12
The ribbon was dried with hot air at 0 ° C. for 2 minutes to obtain a ribbon having a transparent colored layer having a thickness of about 1 μm when dried. Next, an image forming method using these ink ribbons will be described. Confirmation of fixing effect in the state of photographic paper Acid dye system Preparation of photographic paper Prepare an aqueous solution containing barium chloride and modified vinyl acetate in the following weight ratio. The wet paper was coated on a paper having a wet thickness of 100 μm using a wire bar, and dried under reduced pressure at 120 ° C. for 1 hour. Next, the photographic paper having the white receiving layer was passed through a pressure roller heated to 100 ° C. to give gloss. Composition of coating liquid parts by weight Barium chloride 1 Modified vinyl acetate 5 Silicon oil 5 Water-methanol (1/9 volume ratio) 50 Printing test An image was formed in a practical form using the prepared ink ribbon and printing paper. . Specifically, when the ribbon is mounted on the ribbon cassette of the Sony Color Video Printer CVP-G500 and the photographic paper is mounted on the photographic paper cassette and gradation printing is performed, a glossy image with a cyan hue and rich gradation is obtained. Was. Next, after spraying water on this image, the feed speed is 5 mm.
/ Sec at a heating pressure (100 ° C.) between rollers. In order to evaluate the transferability of the obtained image, a film to be transferred was formed to a thickness of 100 μm (at the time of drying) using a wire bar from a coating solution having the following composition. I got it. The coating develops tackiness at room temperature and adheres to the receiving layer but is easy to release. Parts by weight Coating solution Butyral resin 1 Ethanol (solvent) 50 This adhesive film was stuck on the output image and left at 100 ° C. for 30 seconds and then peeled off. A similar transferability evaluation test was carried out on photographic paper containing no precipitant (other components and composition were the same as in the examples). As a result, the image of the present invention maintained an image density of almost 100%, but the conventional image showed only a holding power of about 10% (90% was transferred to the adhesive film), and the image of the present invention was obtained. The fixing effect became clear. Basic dye system (Reference example) Preparation of photographic paper 1 g of acidic clay (Japanese Acid Clay; Wako Pure Chemical) was swelled and dispersed in 100 cc of water.
5 wt% polyvinyl alcohol (polymerization degree 5
00; Wako Pure Chemical Industries, Ltd. 20 g of an aqueous solution was added thereto, followed by ultrasonic dispersion for 1 hour to obtain a white slurry. The slurry was applied on coated paper (thickness: about 200 μm) using a wire bar, dried with hot air, and then dried under reduced pressure at 120 ° C. for 1 hour to obtain a photographic paper having a receiving layer with a thickness of 5 μm when dried. When the photographic paper was immersed in water, swelling of the film was observed, but no re-dissolution was observed. Printing Experiment An image was formed in a practical form using the produced ink ribbon and printing paper. Specifically, the ribbon was mounted on the ribbon cassette of the Sony Color Video Printer CVP-G500, and the photographic paper was mounted on the photographic paper cassette. Glossy image was obtained. Next, the receiving layer was swollen by sliding absorbent cotton holding water on the image. No image flow occurred. A part of this image was put in ethanol (solvent used for preparing the receptor layer) at room temperature, but there was no apparent change after 24 hours. The reflection density of the image before and after the impregnation into the solvent was measured. Although D was slightly reduced from 2.2 to 2.1, no blurring of the image was observed at all, including the portion in contact with the solvent vapor. A similar fixability evaluation test was performed by immersing the image in water, but no elution of the dye was observed, and it was clear that the image was fixed. Table 1 shows the upper and lower limits and preferred ranges of the concentration of the dye in the ink and the concentration of the precipitant in the receiving layer when an acid dye or a basic dye is used.
The upper limit of the dye concentration in the ink is 100% by weight.
This is the case where a dye having a film-forming property is used. In the case of a dye having no film-forming property, a binder resin is required. If the concentration of the dye in the ink is 5 wt% or less, sufficient color formation cannot be obtained. If the concentration of the precipitant in the receiving layer is 90 wt% or more, the precipitant itself does not have a film-forming property, so that film formation becomes impossible. On the other hand, if the content is less than 5% by weight, it is not possible to sufficiently fix the dye on the photographic paper. [Table 1] In the receiving layer, other auxiliary compounds (for example, a fluorescent brightener, a plasticizer, a hygroscopic agent, etc.) may be added as long as they do not inhibit the salt formation reaction between ions. Further, the binder resin does not necessarily have to be water-swellable, and may be a resin that gives a dielectric constant sufficient to cause a salt-forming reaction by itself or a mixture with the low-molecular compound. In that case, no immersion operation is required. Next, a fixing operation was simulated to confirm the behavior of the dye in the receiving layer of the photographic paper. Acid Dye As the dye, sodium copper phthalocyanine tetrasulfonate (Kodak) was used. This dye 1
A part by weight was dissolved in 1,000 parts by weight of ethanol, and 10 parts by weight of a 1% by weight aqueous solution of barium chloride was dropped, and a dark blue precipitate was immediately precipitated, and an almost colorless supernatant was obtained. The precipitate was collected by filtration, washed with a large amount of water, and then washed with acetone, ethyl acetate, and toluene in that order, but no elution of the dye was observed and it was confirmed that the precipitate was formed. It is apparent from the above that a dye amphiphilicized in a high dielectric constant solvent such as ethanol is converted into a pigment by salt formation. This is because if the ink is replaced with an organic cation having a lower ionic binding force than the cation of the laker (precipitant) and used as a dye for an ink ribbon, the dye can be easily dissociated in a high dielectric constant medium in which the ion is easily dissociated. This indicates that ion exchange is performed. Other anionic dyes can be amphiphilicized in a similar manner. The organic cation can be selected from commercially available surfactants, ammonium salts, and phosphonium salts, but the partition coefficient of the resulting (dye) salt in a water-chloroform system (weight ratio 1: 1) is 0.05 or more. It is preferably 10 or less. Examples of the organic cationic surfactant include tetra-n-hexylammonium bromide, tetra-n-butylammonium borofluoride and tetra-n-perchlorate.
Butylammonium, cetyltrimethylammonium bromide, dioctadecyldimethylammonium chloride, myristyldimethyldimethylbenzylammonium chloride, benzyldimethyl chloride- [2- [2- (P-1,1,3,3-tetramethylbutylphenoxy) ethoxy] [Ethyl] ammonium, alkylpyridinium salts, imidazolinium salts and the like. Table 2 lists typical combinations of dyes and precipitants for lakes of general acid dyes. [Table 2] Basic Dye System (Reference Example) Fixing Experiment 0.2 g of acid clay was poured into 20 g of ethanol and dispersed by ultrasonic irradiation for several minutes. Add Rhodamine 6 to this dispersion
Immediately upon addition of 1 cc of a 10 mmol / l ethanol solution of G, a deep orange-red precipitate was formed, giving an almost colorless (slightly orange-yellow fluorescent) supernatant. The colored precipitate was collected by filtration, washed with 100 cc of ethanol to completely remove unreacted dye, and then dried at room temperature.
The interlayer distance of the orange-red powder recovered through such an operation was measured to be 16.03, and the interlayer distance was increased by about 6 from the value of the untreated acid clay (9.77). Further, even when the powder was impregnated with water or another organic solvent (alcohol, MEK, toluene, etc.), no dye was eluted, and it was confirmed that the powder was formed into a pigment. In a similar manner, other basic dyes can be amphiphilicized. The organic anion can be selected from commercially available organic anionic surfactants, but the partition coefficient of the resulting (dye) salt in a water-chloroform system (weight ratio 1: 1) is 0.05 or more and 10 or less. Is preferred. Examples of the organic anionic surfactant include, in addition to sodium p-toluenesulfonate, carboxylate such as soap, N-acylamino acid salt, alkyl ether carboxylate, acylated peptide, alkyl sulfonate, alkylbenzene Sulfonic acid, alkyl naphthalene sulfonic acid, sulfosuccinate, α-olefin sulfonate,
Sulfonates such as N-acyl sulfonates, sulfated oils,
Sulfate esters such as alkyl sulfates, alkyl ether sulfates, alkyl allyl ether sulfates, and alkyl amide sulfates; and phosphate ester salts such as alkyl phosphates, alkyl ether phosphates, and alkyl allyl ether phosphates. No. Table 3 lists typical combinations of dyes and precipitants for laking common basic dyes. [Table 3] As described above, according to the above-described embodiment, in particular, the fixing property can be remarkably improved, and an image having a fixing property comparable to a silver halide photographic image can be obtained. Further, not only the fixing property but also other required properties such as light fastness, hue, and sensitivity can be improved. Further, since the method for manufacturing the ink ribbon in this embodiment conforms to the conventionally used manufacturing method, the conventional manufacturing apparatus can be used as it is. It should be noted that the present invention is not limited to the above-described embodiment, but can adopt various configurations without departing from the gist of the present invention. As described above, according to the present invention,
In particular, the fixability can be dramatically improved, and an image having a fixability comparable to a silver halide photographic image can be obtained.In addition to the fixability, other light resistance, It is possible to improve various properties such as hue and sensitivity, and the method for manufacturing an ink ribbon according to the present invention conforms to a conventionally used manufacturing method, so that a conventional manufacturing apparatus can be used as it is. The benefit of being able to do it.

[Brief description of the drawings] FIG. 1 is a diagram showing an ink ribbon of the present embodiment. [Explanation of symbols] 1 ‥‥ ink layer, 2 ‥‥ support, 3 ‥‥ heat-resistant lubricating layer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-30992 (JP, A) JP-A-61-154995 (JP, A) JP-A-2-4565 (JP, A) JP-A-63- 173692 (JP, A) JP-A-5-17701 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (1)

(57) [Claims] [Claim 1] Ink rib for dye transfer type thermal transfer system
Organic acid cations, in which the inorganic ions of the acid dye have moderate hydrophilicity.
The acid dye having an amphiphilic property substituted by on
The ink layer containing is formed on a support, the organic cation amphiphilic the above acid dye, bromide tetra n- hexyl ammonium borofluoride tetra n- butylammonium perchlorate tetra n- Butylammonium, cetyltrimethylammonium bromide, dioctadecyldimethylammonium chloride, myristyldimethyldimethylbenzylammonium chloride, benzyldimethyl chloride- [2- [2- (P-1,1,3,3-tetramethylbutylphenoxy) ethoxy] [Ethyl] ammonium, an alkylpyridinium salt, and an imidazolinium salt.