JPS6381080A - Production of transfer recording medium - Google Patents

Abstract

PURPOSE:To enable high-quality images to be transferred onto an ordinary paper, by providing a binder on a base, then placing an excess of image-forming elements thereon, and separating and removing the image-forming elements which are not in contact with the binder by a gas flow. CONSTITUTION:A binder 1b is applied to a base 1a, and microcapsules 1c are sprinkled from a hopper 5 onto the layer of the binder 1b, thereby binding the microcapsules to the binder. Of the microcapsules, only those being in contact with the binder are bound, and the other ones are blown away by air jetted from a gas jetting means 7, to be recovered into a recovering container. The gas jetted from the gas flow jetting means is preferably a gas having low activity, e.g., air on N2. Where a thermosetting-type binder is used as the binder, an accelerating effect on the hardening of the binder can be obtained when a heated gas is jetted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a transfer recording medium that can be used in printers, copying machines, facsimiles, and the like.

[Conventional technology]

In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods suitable for each information processing system have also been developed.

One such recording method is the thermal recording method, which has been widely used recently because the device used in this method is lightweight, compact, noiseless, and has excellent operability and maintainability.

Among these thermal recording methods, a thermal transfer recording method has recently attracted particular attention. This recording method is generally
A heat-sensitive transfer medium is used, in which a heat-transferable ink consisting of a colorant dispersed in a heat-melting binder is coated on a sheet-like support, and the heat-transferable ink layer of the heat-sensitive transfer medium is applied to the transfer medium. The ink layer is superimposed on the transfer medium so as to be in contact with the transfer medium, and heat is supplied from the support side of the thermal transfer medium using a thermal head or the like to transfer the melted ink layer to the transfer medium, so that the rotation according to the heat supply pattern forms a recorded image. is formed on the transfer medium. According to this method, plain paper can be used as the transfer medium.

[Problem that the invention seeks to solve]

However, such conventional thermal transfer recording methods are not without drawbacks. The reason is that in conventional thermal transfer recording methods, the transfer recording performance, that is, the image quality, is greatly affected by the surface smoothness of the transfer medium, and while it is possible to print well on highly smooth transfer media, it is possible to print well on transfer media with low smoothness. The print quality on the transfer medium is significantly degraded. Moreover, paper, which is the most common transfer medium, is rather special because it has a high level of smoothness, and ordinary paper has various degrees of unevenness due to entangled fibers. Therefore, in the case of paper with large surface irregularities, the hot-melted ink cannot penetrate into the fibers of the paper during printing and only adheres to the convexities on the surface or the vicinity thereof, resulting in sharp edges of the printed image. The image may not be printed properly, or part of the image may be missing, resulting in poor print quality.

In addition, in conventional thermal transfer recording methods, the ink layer is transferred to the transfer medium only by heat from the thermal head, but there is generally a limit to the amount of heat that can be supplied from the thermal head. In order to convert and supply a large amount of recording signals as heat pulses within a certain amount of time, there is a time lag in cooling the thermal head to a predetermined temperature in terms of the amount of heat pulses during recording.
Furthermore, it has been theoretically difficult to increase the amount of heat supplied from the thermal head in order to prevent thermal stroke between the heat generating segments that constitute the thermal head surface. Therefore, high-speed recording is difficult with conventional thermal recording methods.

In addition, thermal conduction has a slower response than electricity or light, so when recording with a thermal head, it is generally difficult to control heat pulses to the extent that halftones can be reproduced. The heat-sensitive transfer ink layer did not have transfer characteristics capable of expressing gradation, so it was not possible to form a half-tone recorded image.

Therefore, the applicant used a photothermally sensitive polymer material, and when thermal energy and light energy were applied, the reaction of the polymer rapidly progressed and the transfer material changed irreversibly.
An image forming method and a transfer recording medium have been proposed in which an image is formed based on the difference in characteristics according to an image signal, and the image is transferred to a recording medium.

The present invention is a method for manufacturing a new transfer recording medium that solves the above-mentioned conventional problems, that is, it is possible to form a high-quality transfer image on plain paper, which is most commonly used because of its low surface smoothness, and also enables high-speed recording. Another object of the present invention is to provide a method for manufacturing a transfer recording medium that is also capable of halftone recording and multicolor recording.

[Means for solving problems]

That is, the present invention is a method for manufacturing a transfer recording medium in which an image forming element is provided on a base material, which includes a step of providing a binding material on the base material for binding the base material and the image forming element. a step of disposing an excess image forming element on the binder after providing a binder on the base material; This is a method for manufacturing a transfer recording medium, which includes a step of separating and removing the transfer material using a gas flow.

The present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of an embodiment of an apparatus for carrying out the manufacturing method of the present invention.

In this apparatus, 1a is a base material of a transfer recording medium, 1b is a binding material, lc is a microcapsule (image forming element), 2
3 is a base material roll that sends out the base material 1a at a constant speed, 3 stores the binder 1b and transfers the binder 1b to the base material 1a.
4 is a blade for uniformly applying a binder to a desired thickness; 5 is a blade for holding microcapsules, and 4 is a blade for uniformly applying a binder to a desired thickness; 5 is a container for holding microcapsules; Hopper for feeding capsules in small quantities, 6
7 is a mixer for uniformly mixing the microcapsules and supplying the same to the hopper; 7 is a gas jetting means; 8 is a drying oven; 9
is a transfer recording medium collection roll.

A transfer recording medium is manufactured using the above-mentioned apparatus, for example, in the following manner.

That is, first, the binder 1b is applied to a part of the base material 1a while the base material 1a is fed out at a constant speed by the base material roll 2. Microcapsule IC is sprinkled from the hopper 5 onto this layer of binding material 1b to bind the microcapsules to the binding material. At this time, only those in contact with the binding material are bound among the microcapsules, and the other ones are jetted out from the gas jetting means 7 in the subsequent process as shown in FIG. It is blown away by the released air and collected in a collection container (not shown). The resulting base material 1a has microcapsules bound together in a layer with a binding material, and this base material 1a is passed through a drying oven 8 and heated to increase the binding power of the microcapsules. Then, the binding is completed and a transfer recording medium is obtained. The following steps are performed continuously at a constant speed.

Figure 2(a) is a cross-sectional view of microcapsules sprinkled onto the binder in the process described above, and Figure 2(b) is a cross-sectional view of the excess microcapsules being blown away by a gas flow. It is a cross-sectional view of the rest. In this way, the microcapsules not in contact with the binding material 1b are removed, so that the microcapsules are more uniformly provided on the base material 1a.

As described above, in the method for manufacturing a transfer recording medium of the present invention, the image forming element (microcapsule) is placed on the binder after the binding material is provided on the base material, so that the upper surface of the image forming element is In order to obtain a transfer recording medium to which no binder is attached, and to remove image forming elements that are not in contact with the binder among the image forming elements arranged on the binder. , it is possible to obtain a transfer recording medium in which the image forming element is more uniformly arranged on the binder.

The gas ejected from the gas flow ejecting means in the above embodiment is preferably a gas with low activity such as air or N2, and when a thermosetting adhesive such as an epoxy adhesive is used as a binder, heating By blowing out the gas, the effect of accelerating the hardening of the binder can also be obtained.

In the present invention, the method of separating and removing the image forming elements that are not in contact with the binder using a gas flow is not limited to the method of blowing a gas flow as in the above embodiment example, but the method of using a suction device, etc. The image forming element may be separated and removed by generating a gas flow having a suction force using a vacuum cleaner and sucking the image forming element.

In the present invention, the means for providing the binder on the base material include applying the binder using a blade or applicator as described above, spraying the binder, gravure printing, etc. A method can be used.

In addition, the method of arranging the image forming element in one layer of the binder is not limited to the method of sprinkling it alone, but also the method of layering the binder on a separately prepared support,
A method may also be used in which a base material provided with a binder is conveyed in contact with a container containing an image forming element in advance.

Further, in this embodiment, the image forming element was placed on the binder and then dried in a drying oven, but the drying step may be performed after or before the step of separating and removing the excess image forming element. Further, drying is not limited to drying using a drying oven, but natural drying may be used, and if a fast-drying binding material is used, a drying step is not necessary.

Furthermore, the image forming element is not limited to a microcapsule-like one, but may be a granular one that does not have a wall material and is simply agglomerated with a coloring material or the like.

As the binder used in the production method of the present invention, epoxy adhesives, urethane adhesives, acrylic adhesives, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, etc. are preferably used. Also, the base material is PE.
T film, polyamide film, polyimide film, condenser paper, etc. can be used.

The present invention will be explained in more detail below using specific examples.

〔Example〕

A thermal transfer recording medium capable of forming a multicolor image was manufactured as follows.

Production of microcapsules An image forming element was manufactured in the form of a microcapsule.

That is, 1.0 g of the core material components shown in Tables 1 and 2 were first mixed with 20 parts by weight of methylene chloride, and a surfactant having an HLB value of at least 10, such as a cation or nonion, and gelatin Ig were dissolved. Mixed with 200ml of water,
8,000~]OOO with a homomixer heated at 60℃
The mixture was emulsified by stirring with Orpm to obtain oil droplets with an average particle size of 26 μm.

Table 1 Table 2 Stirring was continued at 60° C. for 30 minutes, and the methylene chloride was distilled off to bring the average particle size to approximately 1.5 Ju+. To this, add 20 m4 of water in which gum arabic] g was dissolved, and while slowly cooling, add NH4 ammonia water to pH 11.
A microcapsule thriller was obtained in the above manner, and 1.0 ml of a 20% glutaraldehyde aqueous solution was slowly added to harden the capsule wall.

After that, solid-liquid separation was carried out using a Nutsche filter, and 35
C. for 10 hours to obtain a microcapsule-shaped image forming element. This image forming element was a microcapsule in which the core materials shown in Tables 1 and 2 were covered with a wall material, and had a particle size of 7 to 15 mm and an average particle size of 10.

The core materials used here shown in Tables 1 and 2 have the property of forming an image when thermal energy and light energy are applied thereto. That is, by applying thermal energy and light energy, a reaction is initiated, and the physical properties governing the transfer characteristics change. In other words, the transfer temperature of the image forming element in which the reaction has progressed is higher than that of the image forming element in which the reaction has not progressed. Specifically, when the photoinitiator in the core material shown in Table 1 is heated to 100°C or higher and absorbs light in the band around the peak of curve A in the absorption characteristic graph shown in Figure 3, it generates radicals. It starts a reaction and polymerizes, and due to the reaction, the transfer temperature of the core material increases from 60 to 70°C to 150°C or higher.

This core material exhibits a magenta color when transferred to form an image. On the other hand, when the photoinitiator in the core material shown in Table 2 is heated to over 100°C and absorbs light in the band around the peak of curve B in the absorption characteristic graph shown in Figure 3, it starts a radical reaction. The reaction causes the transfer temperature of the core material to rise from 60 to 70°C to 150°C or higher. This core material exhibits a blue color when transferred to form an image.

Manufacture of transfer recording medium according to the present invention> Using the apparatus shown in FIG. 1 described above, as follows,
A transfer recording medium was manufactured by bonding the above microcapsules onto a base material that was a PET film with a thickness of 6 μm5 and a width of 80 mm.

First, the base material 1a is rolled at a constant speed (1 mm/
m1n), feed the binder 1b onto the base material 1a from the binder coating container 3, and after drying with the blade 4, apply the binder 1b so that the layer thickness becomes approximately 0.3)Lll+.
was applied. All of the following steps were carried out in accordance with this constant speed of substrate delivery.

The binder used here is a two-component epoxy adhesive manufactured by Kanebo N.C., which is a mixture of Evolution E to 1 and Evolution EBI in a 1:1 ratio. did. This binding material does not lose its adhesive properties for several hours even if left at room temperature.

Next, on this adhesive binder layer, a microcapsule-shaped image forming element formed using the core material components shown in Tables 1 and 2 above is mixed in a mixer 6 at a l:1 ratio. From hopper 5, a certain amount (5g
/min).

A cross-sectional view of the laminate formed by sprinkling the image forming elements on the substrate at this point is shown in FIG. 2(a).

Next, when the surface of the laminate on which the image forming element is arranged is conveyed to the gas jetting means 7, air is blown from the gas jetting means 7, so that an image that is not in contact with the binding material is formed. The formed element was blown off from the base material and collected and deposited in a collection container (not shown). After the unnecessary image forming elements were blown off and removed, the laminate had image forming elements arranged in a single layer as shown in FIG. 2(b).

Next, the laminate as shown in Figure 2(b) was heated to 100°C.
A transfer recording medium was obtained by drying the laminate to a desired degree by passing it through a drying path 8 maintained at a constant temperature for 10 minutes. This transfer recording medium was wound up on a transfer recording medium recovery roll 9.

<Experimental Example> Using the transfer recording medium obtained by the method described below, a transfer experiment as described below was conducted.

That is, the PET material of the transfer recording medium is brought into close contact with a hot plate heated to 120°C, and about 25 mm from the surface of the transfer recording layer.
201? manufactured by Toshiba Corporation with the spectral characteristics shown as C and D in Figure 4 from a distance of mm. Health line fluorescent lamp P
L205E and 20W fluorescent lamp FL made by Toshiba Corporation] 0A
70E was irradiated to each desired position over a period of approximately 50 m5 ec. The transfer recording medium after heat irradiation was passed between two wooden rollers that were pressed against each other and overlapped with the recording paper so that the transfer recording layer of the transfer recording medium was in contact with the recording paper whose surface smoothness was about 10 to 20 seconds. .

The pressure between the rollers is set to about 25 kg/m', and the surface temperature of the rollers in contact with the transfer recording medium is set to 90 to 1
It was heated to 00°C. After passing between rollers, when the transfer recording medium and the recording paper were separated, a high quality image of blue and magenta colors was obtained on the recording paper.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to obtain a transfer recording medium in which an image forming element is coated more uniformly on a substrate, and furthermore, a binder is not attached to the surface of the image forming element. By using the transfer recording medium obtained by the present invention, a good transfer image with high image quality can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a manufacturing apparatus used in the manufacturing method of the present invention, and FIG. Figure (b) is a sectional view showing the state after removing unnecessary image forming elements from the state shown in Figure 2 (a), and Figure 3 is a graph showing the absorption characteristics of the photoinitiator in the microcapsules. FIG. 4 is a graph showing the spectral characteristics of a fluorescent lamp. 1: Transfer recording medium 1a: Base material lb: Binder 1c 2. Microcapsule (image forming element) 2: Base material roll 3: Binder coating container 4. 2. Blade 5: Hopper 6: Mixer 7: Gas flow jetting means 8: Drying oven 9/transfer recording medium recovery roll A, B: Absorption characteristics of core material C, D: Spectral characteristics of fluorescent lamp

Claims (1)

[Claims] A method for manufacturing a transfer recording medium comprising an image forming element provided on a base material, comprising: providing a binding material on the base material for binding the base material and the image forming element; a step of disposing an excess image forming element on the binder after providing a binder, and separating only those image forming elements not in contact with the binder with a gas flow. 1. A method for manufacturing a transfer recording medium, comprising the step of removing.