JPS62244697A - Print recording method - Google Patents

Abstract

PURPOSE:To provide the print recording method of good in energy efficiency, capable of enabling the high speed of printing, by a method wherein by linear conductors so arranged as to cross each other pinching an exothermic resistor layer between them, current is caused to flow through the exothermic resistor layer pinched between the crossing parts of those linear conductors and this portion is heated. CONSTITUTION:A thermal transfer recording medium 1 is so constructed that striped electrodes 31, 32 are formed on both surfaces of an exothermic resistor layer 2 and an ink layer 5 is further formed on the surface lower than those via a peeling layer 4. By contacting a needle electrode 82 wit the linear conductor 3 of the first striped electrode 31, a signal current is caused to flow through the exothermic resistor layer 2 and return to a power source 9 from the linear conductor 3 of the second striped electrode 32. Thereby, the exothermic resistor layer 2 pinched between the crossing parts of up and down two wires of linear conductors 3 is heated and the ink layer is heated to be fused. This ink is transferred on to recording paper 6.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a print recording method capable of performing non-impact type recording. The present invention relates to a print recording method for recording an image by transferring molten ink onto recording paper.

``Prior Art'' Various methods have been proposed and put into practical use by converting electrical signals into thermal energy, melting ink using the thermal energy, and transferring the ink onto recording paper to record an image. . Typical examples of such print recording methods include (i) thermal head transfer method, (ii) current transfer method, and (iii) thermal transfer printing method.

Among these, the thermal head transfer method (1) uses a thermal head as a print head, uses a thermal recording medium (ink donor film) coated with low melting point ink on base paper, and slides the thermal head on the base paper side. Let them come into contact with you. A heat pulse is then applied to the ink donor film in accordance with the image information to melt the ink at the corresponding location. A recording paper is superimposed on the ink-applied side of the ink donor film, and the molten ink is transferred to this recording paper. In this case, so-called plain paper that has not been subjected to any processing can be used as the recording paper. The same applies to the following two types of methods.

In the (ii) current transfer method, a large number of needle electrodes are used to energize the ink layer formed on the conductive support.
The gel heat generated at this time is used to melt the ink and transfer it to the recording paper. The transfer method is similar to the thermal head transfer method. In the (iii) thermal transfer printing method, a heating resistor layer, a return electrode, and an ink layer are sequentially provided on an ink support having a certain degree of electrical resistance. Then, a needle electrode is brought into contact with the ink support side, and a current is passed toward the return electrode to partially generate heat in the heating resistor layer. In this way, the ink is selectively melted and transferred to the recording paper.

Among these, (i> thermal head transfer method), thermal pulses are transmitted to the ink layer through a base paper such as capacitor paper that constitutes the ink donor film. Therefore, the thermal conductivity of the base paper has a large effect on the response. With this method, for example, the printing time per pixel (dot) is 1m5.
(Mi! 7 seconds) or more, and the printing speed is relatively slow.

Further, since thermal energy is lost in this base paper portion, less energy is transferred to the ink layer. For this reason, only wax-based materials can be used as the ink material, and there is also the drawback that there is little freedom in selection. Therefore, it is difficult to control the amount of ink transferred to the recording paper, and for example, it is actually difficult to control the size of dots in multiple stages in order to express so-called gradations.

Next (11) In the current transfer method, since a current is passed through the ink layer, a certain level of conductivity must be imparted to the ink layer. For this reason, there is little freedom in selecting coloring materials to be mixed, making color tone control difficult. Therefore, there is a drawback that color recording is difficult. Furthermore, the conductive loss in the support portion that supports the ink layer is large, and its mechanical properties are also poor. Another drawback is that the shape of the printed dots is not stable.

Finally (iii) In the thermal transfer printing method, the current flowing from the needle electrode toward the ink support spreads, causing the heating resistor layer to generate heat over a rather wide area, causing the dots to spread. There is a large leakage current that does not contribute to the ink support, resulting in poor energy efficiency.Furthermore, this method requires a certain amount of resistance in the ink support, so there is also the problem of increased contact resistance between the electrode and the ink support.

On the other hand, Japanese Unexamined Patent Publication No. 56-93585 discloses an example of a print recording method using a non-impact type print ribbon.

FIG. 5 is for explaining the principle of this print recording method. In this method, the print ribbon 20 is comprised of an upper layer 23, a lower layer 24, a conductor layer 25, and an ink layer 26. The lower layer 24 consists of a heating resistor,
The upper layer 23 has a lower electric resistance than this, and the conductor layer 25
Made of a material with slightly higher electrical resistance. and upper layer 2
3, the printed electrode 21 and the ground electrode 22 are placed in contact with each other (the ground electrode 22 and the printed electrode 21 are arranged with a sufficient distance from each other.
When a voltage is applied to 1, a current flows through the upper layer 23, the lower layer 24, and the conductor layer 25 as indicated by the dashed arrow 27 in the figure, passes through the lower layer 24 and the upper layer 23 again, and reaches the ground electrode 22. Due to this current, the lower layer 24 made of the heating resistor locally generates heat (the part marked by the broken line 0). The thermal energy reaches the ink layer 26 via the conductor layer 25 and melts the ink. As a result, the ink is transferred to the recording paper.

``Problems to be Solved by the Invention'' However, in such a print recording method, as shown by the broken line 27 in FIG.
The efficiency of using electrical energy is low. Also,
Since both the printed electrode 21 and the ground electrode 22 come into sliding contact with the upper layer 23, which has a relatively high electrical resistance, the contact resistance increases and electrical energy is wasted here as well.

The present invention has been made with attention to the above points, and an object of the present invention is to provide a print recording method that is energy efficient and can increase printing speed.

"Means for Solving the Problems" The printing and recording method of the present invention consists of a large number of linear conductors extending in a striped manner and electrically separated from each other on one side of the heating resistor layer. a first striped electrode consisting of a first striped electrode, and a large number of linear conductors extending in a striped manner in a direction intersecting the first striped electrode on the other surface of the heating resistor layer and electrically separated from each other. further forming an ink layer on the other surface of the heat generating resistor layer with a peeling layer that facilitates peeling between the second stripe electrode and the second stripe electrode. On the other hand, a recording electrode that is in electrical contact with the linear conductor forming the first striped electrode connects the linear conductor forming the first striped electrode and the second striped electrode. A current is passed between the sandwiched heating resistor layers to generate heat in a part of the heating resistor layer to melt the ink layer and transfer the ink to the recording paper superimposed on the ink layer. That is.

``Operation'' In this way, the linear conductors arranged to intersect with each other with the heating resistor layer in between pass current through the heating resistor layer sandwiched between the intersections of the wire conductors, causing this part to generate heat. let

This heat melts the ink layer and transfers the ink to the recording paper.

At this time, if a low-resistance conductor is used as the linear conductor, the loss of current energy within the linear conductor can be suppressed to a sufficiently low level.

Furthermore, since no current is passed directly through the ink, there is greater freedom in selecting the ink material. This makes it possible to record at high speed and with high quality.

"Example" (Structure of Recording Apparatus) FIG. 1 is a schematic configuration diagram of a recording apparatus that implements the print recording method of the present invention.

This apparatus is an apparatus that superimposes a thermal transfer recording medium 1 and a recording paper 6 on a platen 7 and performs recording using, for example, a recording electrode 8 as shown in a perspective view in FIG. 2.

The thermal transfer recording medium 1 is wound on a reel (not shown) and fed onto the platen 7 in the direction of arrow a, and at the same time, the recording paper 6 is also fed onto the platen 7 in the direction of arrow A.

The thermal transfer recording medium 1 has striped electrodes 31 and 32 formed on both sides of a heating resistor layer 2, and an ink layer 5 formed on the lower surface thereof with a release layer 4 interposed therebetween.

The first striped electrode 31 on the upper surface of the heating resistor layer 2 is formed by a large number of linear conductors 3 electrically separated from each other at equal intervals in parallel to the conveying direction (arrow a direction). be.

Further, the second striped electrode 32 on the lower surface of the heating resistor layer 2 has the same structure as the first striped electrode 31, and the direction of the stripe is substantially perpendicular to the first striped electrode 31. It is formed as follows.

The recording electrode 8 shown in FIG. 2 has a large number of needle electrodes 82 implanted in a base 81, and the needle electrodes 82 are used in contact with the first striped electrode 31. .

Here, the striped electrodes 31 and 32 are preferably made of a material whose volume resistivity is one-tenth or less of that of the heating resistor 2.

Further, the width of each linear conductor 3 is preferably about 1/10 to about 10 times the interval between adjacent linear conductors 3.

If the width of the linear conductor 3 is too narrow, leakage is likely to occur between adjacent linear conductors 3, and if it is too wide, the contact area for contacting the needle electrode 82 of the recording electrode 8 becomes narrow, resulting in contact resistance. In addition to this, the mechanical strength of the linear conductor 3 itself is weakened.

The width of the linear conductor 30 is selected depending on the resolution required for the image to be recorded, and is preferably about 10 μm to 400 μm.

The heating resistor layer 2 has a volume resistivity of 10-2Ω・c.
It is preferable to use a material with a diameter of 104 Ω·cm and a melting point of 25
It is preferable to have heat resistance of 0°C or higher. Such a layer is obtained, for example, by mixing a polyimide resin, polydiphenyl ether resin, polyamide resin, polyesterimide resin, etc. with conductive powder such as carbon powder or metal, or a composite ceramic, and adjusting the resistance value thereof.

The thickness of this heating resistor layer 2 is 5 μm to 1 mm, and preferably 10 μm to 100 μm in consideration of the thermal diffusion control effect.

The release layer 4 has a critical surface tension (γC) of the surface of the recording paper 60.
It is preferable to use a material having lower surface properties and good thin film forming properties. Its thickness is 10 μm or less, preferably 2 μm or less.

Since the critical surface tension (γC) value of plain paper is 4Qdyne/cm, in the case of this release layer 4,
38 dyne/cm or less is preferable.

The ink layer 5 may be thermoplastic and has a melting point of 2.
It is more suitable to use a polymeric substance with a glass transition temperature of 120°C or less as a base material and to mix or dissolve a coloring material thereto for coloring.

(Recording Method) FIG. 3 is an explanatory diagram illustrating the recording principle of the print recording method of the present invention.

In the present invention, the needle electrode 82 is
(FIG. 2) is brought into contact with the linear conductor 3 of the first striped electrode 31. Then, the second striped electrode 3 passes through the heating resistor layer 2 (FIG. 1) in the direction of the broken arrow 12.
A signal current is passed from the 20-wire conductor 3 back to the power source 9.

As a result, the heating resistor layer 2 sandwiched between the alternating portions of the two upper and lower linear conductors 3 generates heat, sends thermal energy in the direction of arrow 13, and heats and melts the ink layer (Fig. 1). . This ink is transferred to recording paper 6 (FIG. 1).

The second striped electrode 32 is connected to one terminal of the power source 9 by placing an appropriate contact (not shown) on the side edge of the back side of the thermal transfer recording medium 1 in FIG.

FIG. 4 is a cross-sectional view showing a state in which the needle electrode 82 is in contact with the first striped electrode 31.

When a pulsed voltage is applied from the power supply 9 in this manner, the signal current flows intensively below the needle electrode 82 as indicated by the arrow in the figure, and is efficiently converted into electrical energy.

Note that the needle electrode 82 is grounded and the second striped electrode 3
Either method may be used, such as selectively applying a signal voltage to the needle electrode 82, or conversely, grounding the second striped electrode 32 and applying a signal voltage to the needle electrode 82. Alternatively, a DC bias voltage may be applied to one side.

According to the above method, it is possible to record with a low contact resistance with the recording electrode 8, a short and simple current path, a fast response, and little power loss.

The response can be about 100 μsec or less. Further, since the heat generating portion can be concentrated, the recording pixel density can be set to about 8 to 16 dots/mm. And 200 to 10 Qerg per dot
It is possible to record with energy of about 100 yen.

Furthermore, since the density of the dots can be controlled with high precision, density expression of 4 to 16 gradations becomes possible.

(Example 1) 35 weight percent electrical conductivity and strength as a heating resistor layer
A 55 μm thick polyimide film containing dispersed bomb black is prepared.

Aluminum is vacuum-deposited to a thickness of 7500 Å on both sides of this film, and photoresist is applied to the upper surface to a thickness of 3 μm. A stripe pattern is printed on this using UV light for 1 minute. This pattern had a width of 60 μm and a pitch of 100 μm. Thereafter, the uncured portion of the photoresist is removed, etched with a sodium hydroxide solution, and then thoroughly washed with water to remove the resist. In this way, striped electrodes were formed on both sides of the heating resistor layer, which were perpendicular to each other.

Next, a thin film of thermosetting resin is applied to one side of the striped electrode and cured by heating to a thickness of 1 μm and a critical surface tension of 27.
An ink release layer of dyne/cm was formed.

On top of this ink release layer, a 4 μm thick layer with a softening temperature of 80°C is applied.
An ink layer containing a thermoplastic resin and a coloring material was formed.

In this way, using a recording electrode having a needle electrode with a wire diameter of 70 μm, a signal voltage of 25 V was applied for 400 μsec.
It was possible to record circular dots with a diameter of 110 μm.

At this time, the pressing force of the needle electrode against the striped electrode was 80
0g/cm'.

Ta.

(Comparative Example 1) The striped electrode of the polyimide film of Example 1 on the side in contact with the needle electrode was removed, and using this, a recording operation was performed under the same conditions.

In this case, no dots could be recorded. On the other hand, when we performed a recording operation by applying a high voltage of 120 μm and 400 μsec, we were able to record dots with a diameter of 120 μm.
Traces of the needle electrode with a diameter of μm remained.

(Example 2) A 5,000-layer-thick nibkel film is formed by electron beam vacuum evaporation on one side of a 17 μm thick polyimide film containing 41 weight percent of conductive carbon black dispersed therein.

A positive photoresist is applied thereon to a thickness of 2 .mu.m, and a high-pressure mercury lamp is used to perform stripe-like exposure with a pitch of 62.5 .mu.m and a width of 40 .mu.m. After that, develop and rinse.
After drying, it was etched with a 60% iron chloride solution to form nickel film stripes with a width of 45 μm.

In addition, on the other side of the polyimide film, by vacuum evaporation method,
A film of aluminum is deposited to a thickness of 6000 mm, with a pitch of 62.5 μm in the direction perpendicular to the stripes of the nickel film, and 4
Exposure was carried out in stripes with a width of 0 μm.

Next, an ink release layer was formed using a millicone thermosetting resin with a thickness of 1 μm and a critical surface tension of 29 dyne/cm.

Here, a 4-μm-thick ink layer was provided, the main component of which was a hot-melt resin having a softening point of 60° C., and 5% by weight of a xanthine-based red pigment dispersed therein.

A line printing head having a stylus electrode with a diameter of 45 μm and an array density of 116 electrodes/mm was pressed onto the nickel stripe of the thermal transfer recording medium obtained in this manner, and 9
Recording was performed by superimposing the ink layer on plain paper with a thickness of 0 μm.

At this time, the platen is made of rubber hard 35 and has a wall thickness of 15 m.
m, using a pressure roller with a diameter of 35 mm, 700 g/am
Recording was performed by applying a signal of 200 μS and 12 V while pressing with a pressing force of .

As a result, dots with a diameter of 75 μm were recorded on the plain paper.

(Comparative Example 2) In Example 2 above, when the nickel layer on the polyimide film was removed and a recording operation was performed under the same conditions,
Unable to record image.

Also, 400. When a 42 V signal was applied, a dot with a diameter of 83 μm was recorded, but damage due to heat during printing was observed on the side of the polyimide film in contact with the needle electrode.

"Variation" The print recording method of the present invention is not limited to the above embodiments.

The directions of the stripes of the first and second striped electrodes sandwiching the heating resistor layer do not necessarily have to be orthogonal as long as they intersect with each other. Further, the directions may all be inclined with respect to the conveyance direction of the recording paper. Various methods other than the above-mentioned embodiments can also be used as a method of applying voltage to these.

"Effects of the Invention" The print recording method of the present invention described above has the following advantages.

■High-speed printing is possible.

Since the heating resistance layer and the ink layer are sufficiently close to each other, heat conduction is good and response is very fast.

In addition, the contact resistance between the needle electrode and the ink support is low.
The driving power is small, and the power supply can be made smaller.

■High quality images can be obtained.

The requirements for the ink layer have been relaxed, and the degree of freedom in selecting the coloring materials to be mixed has increased. Therefore, color materials can be selected with priority given to color tone and fastness, and high-tone color reproduction becomes possible.

Further, most of the coloring materials are thermoplastic resins suitable for carrying out the present invention, and it is possible to select the most suitable coloring material in terms of adhesiveness, quality, color tone, etc. As a result, it is possible to obtain color tones equivalent to or better than that of printing or electrophotography.

■High gradation can be obtained.

Since it has good responsiveness to input signals, it is possible to modulate the human input signal and highly accurately adjust the amount of ink to be transferred.

Therefore, the density of the dots can have high gradation.

Compared to gradation expression by a pattern method using a so-called dot matrix, this method has the advantage that the pixel area can be made smaller and higher resolution can be obtained.

■Energy-saving printing is possible.

The contact resistance between the needle electrode and the striped electrode is low, there is little thermal diffusion, and the electrical resistance of the return electrode etc. can be selected to be sufficiently low, so there is little heat loss.

■It is highly metastatic.

The amount of heat generated can be controlled by the selection of the heating resistor layer, its thickness, the specific resistance of the compounded material, and the current and time applied to it during printing.

Therefore, it is possible to easily respond to environmental temperature changes. It also has a high degree of freedom.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a recording device that implements the print recording method of the present invention, FIG. 2 is a perspective view showing an example of recording electrodes used in this, and FIG. 3 is an explanation of the current path during recording operation. figure,
FIG. 4 is a cross-sectional view of a thermal transfer recording medium suitable for carrying out the present invention and a recording electrode in contact therewith, and FIG. 5 is a cross-sectional view of a conventional thermal transfer recording medium and a recording electrode in contact therewith. DESCRIPTION OF SYMBOLS 1... Thermal transfer recording medium, 2... Heat generating resistor layer, 3... Linear conductor, 4... Peeling layer, 5...・Ink layer, 6
...Recording paper, 31...First striped electrode, 32...
...Second striped electrode.

Claims (1)

[Claims] A first striped electrode consisting of a number of linear conductors extending in a striped manner and electrically separated from each other is provided on one side of the heating resistor layer with the heating resistor layer in between. A second stripe-like electrode is provided on the surface of the heating resistor layer, and the second stripe-like electrode is formed of a large number of linear conductors that extend in a striped manner in a direction intersecting the first stripe-like electrode and are electrically separated from each other. sandwiching the second striped electrode and a peeling layer that facilitates peeling from the second striped electrode on the other surface of the electrode,
While forming an ink layer, recording electrodes electrically contacting the linear conductors forming the first striped electrodes form the lines forming the first striped electrodes and the second striped electrodes. A current is passed between the shaped conductor and the heating resistor layer sandwiched between them, causing a part of the heating resistor layer to generate heat, melting the ink layer, and transferring the ink to the recording paper superimposed on this ink layer. A print recording method characterized by: