JPS6381081A - Production of transfer recording medium - Google Patents

Abstract

PURPOSE:To transfer high-quality images onto an ordinary paper having a low surface smoothness, by providing a binder on a base, then placing image- forming elements thereon to produce a laminate, and applying a pressure on the laminate. CONSTITUTION:A binder 1c is supplied from a binder-applying container 10 onto a base 1a being paid out from a base roll 11 at a fixed velocity, and is applied to the base 1a by a blade 3. Next, a material obtained by uniformly mixing microcapsule-shaped image-forming elements by a mixer is sprinkled, in a fixed quantity at a time, from a hopper 5 onto the layer of the binder, which is tacky. Then, the laminate thus obtained is turned back along a rotary drum 6 so that the side on which the image-forming elements are disposed is directed downward. Further, the laminate is pressed by passing it between rollers 8a, 8b, and is dried by passing it through a drying furnace 9 maintained at 100 deg.C, thereby obtaining a transfer recording medium.

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, facsimile machines, 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 +l'i information processing system have also been developed.

One such recording method is the thermal recording method, which has been widely used recently because the equipment 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 made by dispersing a colorant in a heat-melting +11 binder is coated on a sheet-like support, and the heat-transferable ink layer is applied to a 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 etc. to transfer the melted ink layer to the transfer medium, thereby creating a transferred recorded image according to the heat supply pattern. 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 the cooling of the thermal head to a predetermined temperature during the heat pulse rotation 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 proceeded 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. The present invention also provides a method for manufacturing a transfer recording medium that allows halftone recording and multicolor recording.

(Means for Solving the 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, and the method includes bonding the base material and the image forming element on the base material. a step of providing a binder for binding, a step of providing a binder on a base material and then placing an image forming element on the binder to form a laminate, and applying pressure to the laminate. This is a method for manufacturing a transfer recording medium, which includes a step of imparting.

In the method for manufacturing a transfer recording medium of the present invention, the image forming element is placed on the binder after the binder is provided on the base material, so that the binder is not attached to the upper surface of the image forming element. A transfer recording medium can be obtained.

Further, by applying pressure after placing the image forming element, the image forming element can be arranged smoothly and uniformly on the substrate.

In the present invention, as means for providing the binding material on the base material, methods such as applying the binding material using a blade or applicator, spraying the binding material, gravure printing, etc. may be used. Can be done.

In addition, methods for placing the image forming element on the binder include simply sprinkling it, placing the binder on a separately prepared support, and placing the image forming element on the binder in advance. There is a method in which a base material provided with a binding material is conveyed in contact with the container. If the image forming elements arranged by any of the above methods that are not in contact with the binder are removed by brushing off, the image forming element is almost uniformly bound to the binder. A recording medium can be obtained.

Possible methods for removing it include turning it upside down, blowing it off, or removing it from other parts.

However, as shown in FIG. 2, the laminate formed through such a process has one part of the image forming elements lb, , I
b is in a state where it is sandwiched between other image forming elements and is not attached to the binding material. When the laminate in this state is pressed by sandwiching it between two rollers, it becomes the state shown in FIG. 3. Thereafter, a transfer recording medium is obtained through a heat drying process as required. Drying may be carried out naturally, and if the binder is quick-drying, drying is not necessary.

In the transfer recording medium obtained as described above, the image forming elements are arranged more uniformly, so that a high quality transfer recording image can be obtained.

In the present invention, before or after removing the excess image forming element after placing the image forming element on the binding plate, drying is carried out in a drying oven or naturally. If a binder is used, a drying step is not necessary.

Further, the image forming element may be in the form of particles such as simply hardened coloring material or may be in the form of microcapsules in which the coloring material is covered with a wall material.

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〕

Example 1 A thermal transfer recording medium capable of forming a multicolor image was manufactured as follows.

<Manufacture of microcapsules> An image forming element was manufactured in the form of a microcapsule.

Table 1 Table 2 In other words, 10 g of the core material components shown in Tables 1 and 2 are first mixed with 20 parts by weight of methylene chloride, and then mixed with a surface active material having an HLB value of at least 10 or more, such as a cation or a nonion. 8,000 to 110
The mixture was emulsified by stirring at 000 rpm to obtain oil droplets with an average particle size of 26 μm.

Stirring was continued at 60° C. for 30 minutes, and methylene chloride was distilled off to give an average particle size of about 10 μm. Add 20 ml of water in which gum arabic Ig was dissolved, and add NH4OH (ammonia) water while cooling slowly to adjust the pH.
A microcapsule slurry was obtained by adding 1.0 ml of a 20% glutaraldehyde aqueous solution slowly to harden the capsule walls.

After that, the same liquid was separated using a Nutsche filter, and the liquid was separated using a vacuum dryer.
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 the particle size was 7 to 15 μH, and the -V average particle size was 1O bar.

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 4, 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 100°C or higher and absorbs light in the band around the peak of curve B in the absorption characteristic graph shown in Figure 4, 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> A binder was applied with an applicator onto a base material which was a PET film having a thickness of 6u+ and a width of 80 mm so that the layer thickness was approximately 0.3- after drying.

The binder used here is a two-component epoxy adhesive manufactured by Kanebo N.C. Co., Ltd., and is a mixture of Evolution EAI and Evolution EBI at a ratio of 1:1. This binding material does not lose its adhesive properties even when dried at room temperature.

Next, the above-mentioned first layer
An excess of 18 ffi (1 g) of microcapsule-shaped image forming elements formed using the core material components shown in Tables 1 and 2 was uniformly mixed in a 1=1 ratio.

The excess image forming element was removed to obtain a laminate as shown in FIG. The laminate in this state was passed between two pairs of wooden rollers while applying a pressure of 7 kg/cm2.
The state is now as shown in the cross-sectional view in the figure. In the above steps, the time from applying the binder to placing the image forming element was set to 30 minutes, and the time from placing the image forming element to applying pressure was set to 5 minutes.

When the laminate in the state shown in FIG. 3 was left in an environment of 40° C. for about 8 hours, the binder hardened and the image forming element was fixed to the PET film.

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

That is, the PET side of the transfer recording medium is brought into close contact with a hot plate heated to 120°C, and about 25
mll1llllIll From a distance, a 20W health line fluorescent lamp FL205E manufactured by Toshiba Corporation and a 20W fluorescent lamp FLIO870E manufactured by Toshiba Corporation having the spectral characteristics shown in C and D in Fig. 5 were installed at approximately 50m5ec. Irradiated over a period of time.

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 was set at about 25 kg/m2, and the surface temperature of the roller in contact with the transfer recording medium was heated in advance to 90 to 100°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.

Example 2 A transfer recording medium was manufactured using an apparatus as shown in FIG.

In this apparatus, 1a is a base material of a transfer recording medium, Ic is a binding material, 1b is a microcapsule (image forming element), 1
1 is a base material roll that sends out the base material 1a at a constant speed, l
O is a binder application container that can store the binder IC and apply the binder 1c onto the base material 1a, and 3 is a container for uniformly applying the binder to a desired thickness. It is a blade that can be thinned by bringing it close to the base material, 5 is a hopper that holds the microcapsules and supplies the microcapsules little by little to the applied binding material 1cJ, and 6 is a rotating drum. , 4 is microcapsule 1b
A microcapsule storage container 7 is connected to the microcapsule storage container 4 by a path not shown, and 8a and 8b press the base material on which the image forming elements are arranged from above and below. Laura and 9
1 is a drying oven with a length of 10 m, and 18 is a transfer recording medium collection roll.

A transfer recording medium was manufactured in the following manner using the apparatus described above.

First, the base material 1a is moved at a constant speed of 1m/by the base material roll 11.
The binder coating container 1 is applied to the base material 1a while feeding at the minimum speed.
The same binder 1c as used in Example 1 was supplied from No. 0, and after drying with a blade 3, the binder IC was applied so that the layer thickness was about 0.3-. All of the following -L culms were carried out in accordance with this constant speed of substrate delivery.

Next, a certain amount of the microcapsule-shaped image forming element obtained in Example 1 was uniformly mixed in a 1:1 ratio with a mixer into this adhesive binder layer-L from the hopper 5. (5 g/min).

Next, the laminate is placed on the rotating drum 6 with the side on which the image forming element is not placed facing inside, and rotated for half a turn, so that the side on which the image forming element is placed is facing down. did. In this step, when the laminate rotated about 1/4 of a turn along the rotating drum, the image forming element not in contact with the binder fell and was collected in a collection container. When the laminate was rotated half a rotation along the rotating drum, the image forming elements were arranged as shown in FIG. Next, by passing this laminate between rollers 8a and 8b, a weight of 7 kg/
cm' and then passed through a drying path 9 kept at 100° C. for 15 minutes to dry the laminate to a desired degree, thereby obtaining a transfer recording medium. This transfer recording medium was wound up on a transfer recording medium collection roll 18.

Using this transfer recording medium, we conducted a transfer recording experiment similar to that in Example 1 except that only Fl and 205E were used. As a result, a blue transferred image was obtained on the recording paper, and the remaining transfer recording medium It was magenta in color.

Comparative example polymerization degree 2000. Two types of microcapsules, the same as those obtained in Example 1, were dispersed in an aqueous solution of polyvinyl alcohol 3 with a degree of saponification of 99*, and the thickness was 6 μ'' and the width was 80 mm.
The mixture was coated onto a PUT film of 1.0 mm in diameter, and then left to dry in an environment of 100° C. for 2 hours to obtain a transfer recording medium.

Polyvinyl alcohol was adhered to the area including the upper part of the image forming element of this transfer recording medium.

When a transfer recording experiment similar to that in Example 1 was conducted using this transfer recording medium, a blue transferred image was obtained on the recording paper, but its density was much lower than in Examples 1 and 2. The remaining transfer recording medium was blackish in color.

When this transfer recording medium was observed under a microscope, it was found that the image forming element in which the core material shown in Table 1 was made into microcapsules remained in almost the same state as before the transfer. On the other hand, more than half of the image forming element in which the core material shown in Table 2 was made into microcapsules remained.

(Effects of the Invention) As explained above, in the transfer recording medium obtained by the manufacturing method of the present invention, since the binding material is not attached to the soil surface of the image forming element, the rolling rate of the image forming element is Furthermore, since the binder is not transferred, it is possible to obtain a good transferred image with high image quality.Also, since the image forming element is arranged evenly and in a single layer, even higher quality transferred images can be obtained. You can get it.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment of an apparatus for carrying out the manufacturing method of the present invention, and FIG. 2 is a schematic cross-sectional view showing a state when an image forming element is placed on a substrate. and the third
The figure is a schematic sectional view showing the state of the product in the state shown in Fig. 2 after being pressed from 10F, and Fig. 4 is a graph showing the absorption characteristics of the photoinitiator in the microcapsule (image forming element). 5 is a graph showing the spectral characteristics of a fluorescent lamp. 1: Transfer recording medium 1a: Substrate Ib, Ib, , Ib2: Image forming element 3 Ni blade 4: Microcapsule storage container 5: Hopper 6: Rotating drum 7: Collection container 8a, 8b Two rolls (for pressing) 9: Drying oven 10: Binder coating container 11: Base material roll 18: Transfer recording medium recovery rolls 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 transfer recording medium comprising the steps of: forming a laminate by disposing an image forming element on the binding material after providing a binding material; and applying pressure to the laminate. manufacturing method.