JP2764963B2 - Printing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print recording method for converting an electric image signal into thermal energy and transferring an ink image to a transfer material.

2. Description of the Related Art Conventionally, as a print recording method for forming an image by converting an image electric signal into thermal energy, dissolving an ink layer with the thermal energy, and transferring it to transfer paper, a thermal print recording method, for example, A signal current is applied by a needle-shaped electrode from the ink support side to a print recording medium having a heating element layer and a return circuit provided on a resistive ink support, and a current circuit is formed in the ink recording medium to generate heat, thereby forming ink. A method of transferring a hot-melt spot as a spot (for example,
Or a current recording method, for example, by pressing a print recording head having a recording electrode and a return electrode on one surface against an ink recording medium having a heating element layer, and applying an electric signal from a needle electrode. A method is used in which a heating element layer is heated in the formed area, the ink in the area is melted and transferred to transfer paper (for example, JP-A-59-171666).

Problems to be Solved by the Invention In these systems, the needle-shaped electrode and the surface of the ink recording medium make electrical contact by sliding contact,
Due to the sliding, vibration occurs and a slight discharge phenomenon may occur. Therefore, (1) dust or dust in the air tends to adhere electrostatically to the surface of the ink recording medium. (2) When powder ink is used, the powder ink scatters inside the apparatus, and (3) Foreign matter such as dust and dirt adheres to the surface of the ink recording medium because the ink recording medium is rotated, so that abrasion powder is easily generated due to friction at a contact portion. I do.

These foreign substances such as dust and dirt cause various obstacles when the print recording head is pressed against the ink recording medium during print recording as described above. This causes a problem that a good contact state cannot be maintained and the print quality is reduced.

As a method for removing foreign substances such as dust and dirt, a cleaning method using an air blow and a cleaning method using a brush can be adopted. However, these methods require a large space, are expensive, and have a sufficient cleaning efficiency. Not.

By the way, on the surface of the ink recording medium, a polymer material,
Since there is a thin film metal, ceramic material, etc., in order to remove foreign substances such as dust and dirt as described above, low pressure and high cleaning efficiency are used so that the amount of wear of the material existing on the surface does not increase. It is required to adopt a cleaning method.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described situation in the related art, and it is an object of the present invention to reduce the influence of foreign matter such as dust and dirt as much as possible when a print recording head is pressed against an ink recording medium. It is intended for.

That is, an object of the present invention is to provide a print recording method in which a recording electrode of a print recording head can always maintain a good contact state with an ink recording medium.

Another object of the present invention is to provide a print recording method capable of obtaining a high-resolution, high-quality recorded image.

Means and Actions for Solving the Problems The object of the present invention is to provide an image electric signal by pressing a print recording head against an ink recording medium having at least a heating element layer and a heat-meltable ink layer or a thermal sublimation dye ink layer. And applying a heat-meltable ink layer or a heat-sublimation dye ink layer on the transfer material in response to an image electric signal. This can be achieved by cleaning the surface of the anisotropic conductive layer of the ink recording medium using a cleaning roll having a sticky surface made of a material having rubber-like viscoelasticity.

In the present invention, the surface of the cleaning roll preferably has a low surface energy of a critical surface tension of 35 dynes / cm or less.

Next, the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram for explaining one embodiment of the print recording method of the present invention.

In the figure, reference numeral 1 denotes a print recording head, and an ink recording medium 2
Is configured to apply an image electric signal by sliding on the surface of the image. The ink recording medium 2 includes an anisotropic conductive layer 21 and a heating element layer.
22, a return power layer 23, an ink release layer 24, and a heat-meltable ink layer or a thermal sublimation type dye ink layer 25. Reference numeral 3 denotes a cleaning roll having an adhesive surface, which is disposed so as to rotate in contact with the anisotropic conductive layer surface of the ink recording medium. A detaching blade 4 is pressed against the surface of the cleaning roll, and the detached foreign matter is collected in a dust collecting box 5. Reference numeral 6 denotes a transfer paper, which is pressed against the heat-meltable ink layer of the ink recording medium by an elastic platen roll 7. Reference numeral 8 denotes a back-up backup roll that presses a back surface provided at a position facing the cleaning roll 3.

The ink recording medium 2 is conveyed to the printing unit by a driving unit (not shown), but comes into contact with the cleaning roll 3 having an adhesive surface disposed in front of the printing unit and adheres to the anisotropic conductive layer surface of the ink recording medium. Foreign matter, such as dust and dirt, transferred to the surface of the cleaning roll and is cleaned. The foreign matter transferred to the cleaning roll surface is separated from the cleaning roll surface by the separation blade 4 and collected in the dust collection box 5. Next, in the printing section, in the printing section, an image electric signal is applied by the print recording head 1, and the heating element layer 21 generates heat in accordance with the image electric signal, and the heat-meltable ink layer or thermal sublimation in that portion. The dye ink layer 22 melts or sublimes and is transferred onto the transfer paper 6.

The cleaning roll used in the present invention is preferably formed of a material having at least a surface having rubber-like viscoelasticity, and has a rubber hardness in a range of 15 to 60 °. As the cleaning roll, one having a critical surface tension of 35 dynes / cm or less is preferable.

As a material constituting the surface of the cleaning roll,
An elastic material whose temperature range is between 0 ° C. and 40 ° C. is located between the glass transition point and the melting point is used. Typical examples thereof include silicone elastomers, fluorine-containing urethane rubbers, and the like. Those having the following.

In the present invention, foreign matter such as dust and dirt adhered to the surface of the cleaning roll by adhesive force may be detached from the surface by the detachment blade 4 pressed against the surface, but adhere to the surface of the cleaning roll. Foreign substances such as dust and dirt are often made of thermoplastic resin such as powdered ink. Therefore, as shown in FIG. 2, use a cleaning bar such as a heated metal bar that can be pressed against the surface of the cleaning roll and rotated. Is preferred. In this case, it is preferable to use a cleaning bar whose surface has a critical surface tension of 40 dynes / cm or more and is heated to 130 ° C. or more. Because, when such a cleaning bar is pressed against the surface of the cleaning roll, the thermoplastic resin in the adhered foreign matter is liquefied and easily transferred from the cleaning roll surface to the cleaning bar, and the cleaning roll surface is initialized. Regenerate to a clean state. In that case, dust other than the thermoplastic resin is absorbed by the thermoplastic resin and cleaned together.

In FIG. 2, the cleaning roll 3 has an adhesive layer 10 on the surface, and is provided with a rotatable heating metal bar 11 having a built-in heating heater 12 pressed against the surface. Reference numeral 9 denotes a foreign material, and reference numeral 13 denotes a metal blade for releasing the foreign material transferred to the surface of the heated metal bar. The separated foreign material is collected in the dust collection box 5.

The cleaning roll used in the present invention has a diameter of
Those having a range of 20 mm to 200 mm are preferable. If the diameter is too large, it is not preferable because the entire apparatus becomes large, and if the diameter is too small, when a cleaning bar is used,
The heat cannot be released, the temperature of the cleaning roll itself increases, and the ability to collect foreign substances decreases.

In the present invention, the surface of the cleaning roll preferably has a critical surface tension of 35 dynes / cm or less.
Those having a range of 8 to 30 dynes / cm are particularly preferred. When the critical surface tension is higher than 30 dynes / cm, the cleaning ability when using a cleaning bar is reduced, especially 35 dynes / cm.
If it is higher, the cleaning ability is significantly reduced. In addition,
When the critical surface tension is lower than 18 dynes / cm, when the ink recording medium is transported at a high speed, the rotation of the cleaning roll is also performed at a high speed. May be scattered.

Next, the ink recording medium used in the present invention will be described.

A typical layer configuration of the ink recording medium of the present invention comprises an anisotropic conductive layer, a heating element layer, a return power layer, an ink release layer, a heat-meltable ink layer or a thermal sublimation dye ink layer.

The anisotropic conductive layer has a function of reducing an energizing loss due to energizing resistance during energizing in the thickness direction, and also reducing heat loss and damage due to contact resistance between the needle electrode and the surface of the ink recording medium. It may be a conductive isolated pattern layer made of electrodes, or a layer in which a conductive path made of a conductive substance such as metal powder or conductive ceramic particles is formed in an insulating material such as ceramic or synthetic resin. There may be.

In the ink recording medium of the present invention, when the anisotropic conductive layer is a layer made of a conductive isolated pattern, the heating element layer may have a function as a support. In the case of a layer, the anisotropic conductive layer itself may have a function as a support, and a thin film heating element layer may be formed on one surface thereof.

The heating element layer is a layer for generating electric current from the anisotropic conductive layer by Joule heat, melting the ink and transferring it to the transfer material, for example, by dispersing a conductive substance such as carbon and metal powder. Conductive layer made of heat-resistant resin (polyimide resin, polyimide amide resin, silicone resin, fluorine resin, epoxy resin, etc.), high resistance material such as ZrO ₂ , Al ₂ O ₃ , SiO ₂ and Ti, Al, Ta For example, a thin film formed using a conductive material such as Cu, Au, and Zr is used. The volume resistivity of the heating element layer is preferably set in the range of 10 ^-2 to 10 ² Ω · cm, and the film thickness thereof is preferably set in the range of 1000 to 500 µm.
Those in this range have excellent characteristics in film deposition stability, film adhesion, and the like.

The return electrode layer diffuses the current flowing into the heating element layer,
An electrode to be refluxed, having a volume resistivity of 10 ^-1
It is composed of a material of Ω · cm or less, and is formed by vapor deposition, sputtering or other thin film forming methods. The film thickness is
It is preferable to set the thickness in the range of 500 to 5 μm, especially 100
The range of 0 ° to 2000 ° is preferable in terms of heat leakage and necessary conductive characteristics.

The ink release layer is a layer adjusted to a critical surface tension such that ink transfer can be performed well even at a low printing energy, and is a thin film having a low surface energy function. It has a critical surface tension lower than the surface energy. For example, when the transfer material is plain paper, the critical surface tension needs to be 40 dynes / cm or less. In addition, it is preferable that the critical surface tension of the ink release layer is lower than the surface tension of the heat-meltable ink layer because a greater effect can be obtained in the transition phenomenon of the heat-meltable ink layer. The thickness of the ink release layer itself is preferably set as thin as possible in the range of 500 ° to 6 μm from the viewpoint of energy transfer efficiency. As a material constituting the ink release layer, for example, a thermosetting silicone resin, a fluorine-containing resin, or the like can be used.

The hot-melt ink layer is formed by dispersing a known dye or pigment such as carbon black in a thermoplastic resin having a melting point of 140 ° C. or lower. The thickness of the hot-melt ink layer is 1 to 15
It is preferable to set it in the range of μm. The thermal sublimation dye ink layer is composed of a sublimable dye and a small amount of resin. As the sublimable dye, for example, azo dyes, indoaniline dyes, and cyanivinyl dyes are used.

Examples Next, the present invention will be described with reference to examples.

Example 1 A Cr layer having a thickness of 7000 mm was formed on both surfaces of a conductive polyimide film having a thickness of 30 μm by a vacuum deposition method. Next, a photoresist was formed on the Cr layer and dried at 90 ° C. for 8 minutes to form a 1.2 μm-thick resist film. This resist film was exposed through a mask having a rectangular pattern of 15 μm square at a pitch of 20 μm on the entire surface, developed, and heated to cure the resist film. Next, using dilute hydrochloric acid, etching is performed in the presence of zinc particles.
Cr was removed. After washing thoroughly, put in an acetone bath,
Ultrasonic waves were applied to remove the resist film, thereby completing the formation of an anisotropic conductive layer composed of a conductive pattern.

Next, a thermosetting silicone resin is applied on the Cr layer on the other surface of the conductive polyimide film, and is heated and cured at 150 ° C. for 1 hour to form a 0.4 μm-thick ink release layer having a low surface energy. Formed.

Both ends of the obtained laminated film were adhered to form an endless belt. An endless belt-shaped ink recording medium was prepared by providing a 6 μm-thick colored heat-meltable ink layer mainly composed of a thermoplastic resin having a melting point of 95 ° C. on the ink release layer.

Using the above-mentioned ink recording medium, printing was performed as shown in FIG. In FIG. 3, the ink recording medium 2 is transported to the printing unit by the transport rolls 14,
By passing between the cleaning roll 3 having an adhesive surface provided in front of the printing section and the back-up backup roll 8, foreign substances such as dust and dust adhering to the surface of the anisotropic conductive layer are cleaned. The foreign matter is transferred to the heated metal bar 11 and collected in the dust collection box 5. Next, on the elastic platen roll 7, the image is transferred to the transfer paper 6 from the paper roll by a signal input from the print recording head 1. After the printing and recording are completed, the ink recording medium 2 is reproduced by applying the powdery hot-melt ink by the powder ink supply unit 16 and then homogenizing by the surface adjusting unit 15, and one printing cycle is performed. finish.

In the above case, the cleaning roll is located at a position 20 mm before the contact point between the print recording head and the ink recording medium,
It was arranged so as to be in pressure contact with a nip width of 1.5 mm. The cleaning roll has an outer diameter of 60 mmφ, is made of a silicone elastomer material having a rubber hardness of 30 mm as an elastic body, has a thickness of 2.0 mm, and has a critical surface tension of 22 dynes / cm (by the Zisman plot method). used. The ink recording medium is conveyed at a linear velocity of 95 mm / sec, while the cleaning roll has an outer diameter of 50 made of aluminum as a cleaning bar.
A rotatable pipe having a diameter of 2 mm and a thickness of 2 mm, which was provided with a heater at the center of the pipe, was pressed against the pipe. The surface temperature of the cleaning bar was set to 140 ° C., and a foreign matter removing operation was performed.

400μs pulse width from 8 stylus / mm stylus head
An image electric signal having a current amount of 24 mA was applied by pressure to the anisotropic conductive layer, and the image was recorded on a recording paper in contact with the back pressure roller.

After the printing, the heat-meltable ink was supplied to the ink transfer mark of the ink recording medium, the colored heat-meltable ink layer was leveled, temporarily fixed, and reproduced.

When the above-described printing cycle was continuously performed for 15 hours, no stain was generated on the contact portion of the print recording head, and the shape of the printing dot was maintained within a dot diameter variation of ± 10 °.

Comparative Example 1 Using the same ink recording medium as in Example 1, print recording was performed in the same manner. However, no cleaning roll was provided. When a continuous printing operation was performed in the same manner as in Example 1, at the time of the continuous printing operation for 15 hours, dust and powdered ink adhered to the periphery of the print recording head. The dots also had a variation in shape of σ = 21 μm (average dot diameter 125 μm), resulting in an uneven printed image.

Advantageous Effects of the Invention As described above, the present invention provides a method for cleaning an anisotropic conductive layer surface of an ink recording medium having a sticky surface made of a material having rubber-like viscoelasticity before pressing the print recording head against the ink recording medium. Since cleaning is performed using a roll, foreign matters such as dust and dirt on the ink recording medium can be efficiently removed without damaging the ink recording medium. Therefore, according to the present invention, the following effects are produced.

1) The reliability of the contact of the print recording head with the ink recording medium is increased. 2) Since the noise discharge can be controlled, the life of the ink recording medium and the print recording head is prolonged. 3) Since the signal noise is reduced, the reproducibility of the printing dots is improved, and a high-resolution and high-quality image can be obtained. 4) Fluctuation of the printing drive pulse is reduced, the life of the circuit is extended, the circuit itself can be simplified, the cost can be reduced, and the reliability can be improved.
5) High-speed print recording becomes possible.

[Brief description of the drawings]

FIG. 1 is an explanatory view for explaining one embodiment of the printing and recording method of the present invention, FIG. 2 is an explanatory view for explaining another embodiment of the cleaning roll used in the present invention, and FIG. 1 is a schematic configuration diagram of a print recording process to which the present invention is applied. 1 print recording head, 2 ink recording medium, 3
Cleaning roll, 4: Removal blade, 5: Dust collection box, 6: Transfer paper, 7: Elastic platen roll, 8
… Back-up roll, 9 Refuse, 10 Adhesive layer, 11 Heated metal bar, 12 Heater, 13…
... Metal blade, 14 ... Conveying roll, 15 ... Smoothing unit, 16 ... Powder ink supply unit, 21 ... Anisotropic conductive layer, 22 ... Heating element layer, 23 ... Return electrode layer, 24 ... ... Ink release layer, 25 ... Heat-meltable ink layer (or thermal sublimation dye ink layer).

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 29/00 B41J 2/325

Claims (2)

(57) [Claims] An image electric signal is applied by pressing a print recording head to an ink recording medium having at least a heating element layer and a heat-fusible ink layer or a heat sublimation type dye ink layer to apply an image electric signal to a transfer material. In a print recording method comprising transferring a heat-meltable ink layer or a thermal sublimation type dye ink layer corresponding to the above, the print recording head is pressed against the ink recording medium before the surface of the anisotropic conductive layer of the ink recording medium. Using a cleaning roll having a sticky surface made of a material having rubber-like viscoelasticity. 2. The print recording method according to claim 1, wherein the surface of the cleaning roll has a low surface energy having a critical surface tension of 35 dynes / cm or less.