JPS62218148A - Recording head and recording method using recording head - Google Patents

Abstract

PURPOSE:To enable high-speed recording without generation of a blur or a fog in recorded images by providing a heating means to heat selectively the neighborhood of plural ink passage holes in a container and connecting a pressure application means to apply pressure to the interior of the container in response to the heating. CONSTITUTION:If an image signal is input as an external signal, it enters a drive controller 6, which in turn, stores the image signal input temporarily, converts it to a signal suitable for writing and applies the converted signal to between electrodes 1b as a voltage pulse. This causes a thermal resistor 1c between the electrodes 1b to heat, resulting in the heating of ink near the thermal resistor to becomes less viscous. If a transmitted signal contains a write signal, an air pressure application pulse generates from a diffusion controller 7 and a constant pressure is applied to ink inside a recording head 1. Consequently the less viscous ink percolates from a dot 1d and an ink image is transferred to a recording medium 2. This enables high speed recording and smooth ink run. In addition, in case of a non-recording line, the pressure application can be eliminated, thus preventing an erroneous transfer and also generation of a fog and other defects effectively.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a recording head that can be used, for example, in an image processor, an electronic typewriter 1, a facsimile machine, various bulletin boards, etc., and a recording method using the recording head. be.

<Prior Art> The thermal transfer recording method has been widely used in recent years because of its general features such as the fact that the apparatus used is a small cabin and does not make any noise, and also because it is capable of recording on fitI1 paper.

The thermal transfer recording method described above uses an ink film formed by coating a heat-melting ink on a support, heats the ink film in an image pattern with a recording head, and transfers the molten ink to recording paper. .

However, the above-mentioned thermal transfer recording method has drawbacks such as high running costs since the ink film once used must be disposed of, and the processing of the used ink film is complicated.

To improve the above-mentioned drawbacks, for example, as shown in FIG. 5, there is a system in which an ink passage hole 1d for ink to pass through is provided in a heating element 1c of a recording head 1 used for angry heat recording. No. 59-118493, JP-A-59-2
No. 25990).

In this method, an ink container is filled with semi-solid ink, pressure is constantly applied to the ink in the direction of the passage hole, and when a heating element lc is heated, the ink near the heating element softens and lowers the viscosity. , ink passes through the passage hole 1d. Therefore, an ink image is recorded on the recording medium 2 by using a recording head in which the passage holes 1d are formed in an array, and selectively applying a heating signal to each heating element 1c.

According to the above configuration, there is no need to use an ink film, and since the ink can be directly heated without using a film, there are advantages such as good thermal energy efficiency.

<Problem that the invention seeks to solve> However, the above configuration is not without drawbacks.

As mentioned above, while constantly applying pressure to the ink in the container,
In a configuration in which the passage hole portion is heated to allow ink to pass through, the ink passage hole and the recording medium come into direct contact and slide relative to each other in that state, resulting in trailing or trailing on the recorded image.
Or capri tends to occur.

That is, in the above structure, since the heat capacity of the ink normally used is relatively large compared to the heating element, when the ink is heated and melted or softened, it retains the heat for a while to store its own heat. For this reason, even if the temperature of the heating element decreases, the ink remains in a softened state, and trailing tends to occur during ink transfer.

Furthermore, since pressure is constantly applied to the ink as described above, the ink may erroneously come out of the ink passage holes in areas other than those to be recorded, making it easy for capri to occur.

The present invention solves the above-mentioned conventional problems and provides a printhead that can perform high-speed printing without causing trailing or fogging in the printed image, and a printing method using the printhead.

<Means for Solving the Problems> The means of the present invention for solving the above-mentioned conventional problems is to provide a plurality of ink passage holes consisting of through holes in a container capable of storing ink inside, and to Recording is performed using a recording head which is provided with a heat generating means for selectively heating the vicinity thereof, and is connected to a pressurizing means for applying pressure within the container in response to the heat generated by the heat generating means. It is characterized by ε.

Effect> According to the above means, the ink near the ink passage hole is heated by the heat generating means according to the recording information, and the softened ink is transferred and recorded on the recording medium. Further, since pressure is applied to the ink in the container by the pressurizing means in response to the heating of the ink, the ink can be transferred to the recording medium even if the ink near the center of the ink passage hole does not have a sufficiently low viscosity. Therefore, it is not necessary to excessively heat the ink, so that trailing of the four inks can be prevented and high-speed recording can be performed.

Furthermore, when the ink is not heated, the pressure is not applied to the ink, so ink will not accidentally come out of the ink passage holes, and fogging will also be prevented.

<Example> Next, an example of a recording method to which the above means is applied will be described.

FIG. 1 is a schematic explanatory diagram of a recording configuration according to an embodiment, FIG. 2 is a perspective explanatory diagram of a recording head, and FIG. 3 is an explanatory diagram of a main part of a writing section of the recording head.

In the figure, l is a recording head formed in a cylindrical shape,
As shown in FIG. 2, it is a cylindrical container-shaped cane with a part that can come into contact with the recording medium 2, and inside it is a so-called thermal melting rod that maintains high viscosity at room temperature but decreases in viscosity at high temperatures. The container is configured to be able to accommodate ink that has a property of softening (including softening and sublimation).

The contact portion with the recording medium 2 is as shown in FIG.
It is composed of a heat-resistant substrate 1a made of ceramic such as 1t(h) or polyimide, and electrodes 1b made of an alloy such as nickel, chromium, or gold, or copper or aluminum are provided on the substrate 1a at minute intervals. Between the electrodes lb, an electric heating resistor 1c made of nitride tank, ruthenium oxide, carbon sheet, etc. is deposited, printed, or
Alternatively, the pasting is provided by etc., and the heat generating means is constituted by this. Incidentally, an insulating protective film 1k is provided on the electrode lb, if necessary.

Furthermore, at the position of the heating resistor 1c sandwiched between the molds i1b,
Ink passage holes (hereinafter referred to as r-dots J) ld are bored through the heating resistor 1c and the base 1a.

That is, the ton) ld is formed in an array at the contact portion with the recording medium 2, and when a predetermined electrode 1b is energized, the heating resistor IC located between the electrodes 1b generates heat, and as a result, the ton ) ld or its vicinity is configured to be heated.

Further, the electrode 1b of the recording head 1 is connected to an energizing power source 5 via a connector 3 and a signal cable 4, and a drive controller 6 is connected to the energizing power source 5.

Therefore, when an image signal is input to the drive controller 6 as an external signal, the electrode 1 is placed at a predetermined position according to the image signal.
A voltage is applied to b.

Furthermore, a diffuse controller 7 is connected to the drive controller 6. The diffuse controller 7 generates air pressure application pulses in response to signals from the drive controller 6 which operates in response to image signals. The pulse is then transmitted to a diffusion regulator 8, and the regulator 8 is configured to apply a constant air pressure into the container of the recording head l in response to the pulse.

Therefore, by pressurizing the inside of the recording head 1 from the diffusion regulator 8, the heating resistor 1 is
A constant pressure is applied in synchronization with the energization period to c.

In addition, numeral 9 in the figure is a pressurizing tube that connects the diffusion regulator 8 and the recording head 1.

The recording medium 2 may be paper, polyethylene, polypropylene,
It is made of a sheet material having a surface of polyester, Teflon, etc., and is conveyed in the direction of arrow a by a platen roller IO that rotates intermittently or continuously depending on recording.

Next, the ink to be filled into the recording head 1 will be described. Typically, a heat-melting ink can be used. This hot-melt ink is made by dispersing or dissolving a coloring agent in a hot-melting binder, and the melt viscosity, adhesive strength, etc. are adjusted by adding an elastomer or the like to the hot-melting binder.

Heat-melting binders include various conventionally used binders such as natural or synthetic wax resins, etc.
Or a mixture of two or more types can be used.

For example, if a heat-melt binder having supercooling properties is added to the heat-melt binder together with an oil agent, etc., good recorded images can be obtained even if there is a distance between the heating position and the ink transfer position to the recording medium 2. can be obtained. Note that a binder with supercooling properties is defined as a binder that, once heated above the melting point (softening point) and cooled from the molten or softened state, it remains for a certain period of time even at a temperature below the original melting point or softening point. refers to a substance that maintains a molten or softened state, and is itself known.

The heat-melting binders that make up the ink include natural waxes such as spermaceti wax, beeswax, lanolin, carnauba wax, candelilla wax, montan wax, and ceresin wax, petroleum waxes such as paraffin wax and microcrystalline wax, oxidized waxes, and esters. Wax, low molecular weight polyethylene, synthetic wax such as Finscher-Tropsch wax, higher fatty acids such as lauric acid, myristic acid, valmitic acid, stearic acid, behenic acid, higher alcohols such as stearyl alcohol and behenyl alcohol, fatty acid esters of sila sugar, sorbitan Esters such as fatty acid esters, amides such as oleylamide, polyamide resins, polyester resins, epoxy resins, polyurethane resins, polyacrylic resins, polyhinyl chloride resins, cellulose resins,
By appropriately mixing elastomers such as polyvinyl alcohol resin, petroleum resin, phenol resin, polystyrene resin, natural rubber, styrene-butadiene rubber, isoprene rubber, and chloroprene rubber, or a plasticizer, and an oil agent such as mineral oil or vegetable oil, It is used by controlling the melting temperature and melt viscosity.

As the coloring agent constituting the heat-melting ink together with the heat-melting binder, all dyes and pigments commonly used in printing or other recording methods, such as carbon black, can be used, and these dyes and pigments may be used alone or in combination. The content of the coloring agent used in combination of two or more types is 1 to 1 in the above ink.
40% is preferred.

Next, the operation when the recording head 1 is filled with the ink and recording is performed will be described.

First, an image signal is input as an external signal from an external facsimile, computer, memory, or the like. This image signal is input to the drive controller 6, and when a start signal among these signals is input, the platen roller 10 is rotated by a motor (not shown) in FIG. 2 to convey the recording medium 2 in the direction of arrow a.

Next, the drive controller 6 temporarily stores the image signals inputted in time series, and stores them in the line memory (1) or two or more lines.

Furthermore, the image signal stored in the memory is converted into a signal suitable for writing by the recording pad 1 and then sent to the energizing power source 5.
and is applied between the electrodes 15 at predetermined positions as a write voltage pulse for each line from the power source 5.

As a result, a current flows through the heating resistor 1c between the electrodes 15 to which the voltage is applied (the writing dot portion), generating heat, and the ink near the heating resistor is heated and its viscosity decreases. On the other hand, since the resistor IC between the electrodes 15 to which no voltage is applied (non-written dot portion) does not generate heat, the ink in the dot portion remains highly viscous.

At this time, the memory of the drive controller 6 is searched to see whether or not the signal transmitted to the energizing power source 5 includes a write signal (voltage application signal) in one line, and if it does, the energizing power source Simultaneously with or before and after sending one line's worth of signals to 5, an air pressure application pulse is generated from the diffuser controller 7, and a constant pressure is applied to the ink in the recording head 1 via the diffuser regulator 8. is applied.

The air pressure is 501w/- to 5kgw/-, depending on the viscosity of the ink to be filled, or the viscosity when melted, etc.
A practical amount is preferably about 50 g/- to 1 kgw/-.

When pressure is applied in response to the heating of the ink, the ink with reduced viscosity oozes out from the dots ld, and an ink image is transferred onto the recording medium 2.

By applying pressure in conjunction with applying heat to the ink as described above, it is possible to speed up recording, improve ink cutting, and widen the selection of ink supply and recording medium 2. Become.

That is, if no pressure is applied to the ink during the recording, the ink must have a sufficiently low viscosity when it passes through the dots 1d.

Therefore, it is necessary to heat the ink sufficiently for this purpose, which requires a considerable amount of thermal energy, and it takes time to cool the heating element, which slows down the recording speed. If it protrudes, it tends to cause tailing.

However, when pressure is applied in a pulsed manner in response to the heating of the ink as in this example, if the viscosity of the ink near the heating resistor that generates heat decreases to some extent, even if the viscosity does not decrease sufficiently to the vicinity of the center of the hole. Ink transfer onto the recording medium 2 is performed smoothly. Therefore, there is no need to excessively heat the ink, and high-speed recording becomes possible.

Furthermore, by stopping the pressure application after each line is recorded, the contact between the ink and the recording medium 2 is quickly broken due to the surface tension of the ink, so that the ink runs out easily.

Furthermore, when pressure is applied in response to heating as described above, the ink with reduced viscosity expands and contracts appropriately from the dot ld, so that the ink can be transferred well even to the recording medium 2 with low smoothness, for example. Ru. Furthermore, it is possible to perform better transfer even to a recording medium 2 having an extremely low surface tension, such as polyethylene used in a so-called whiteboard.

Here, the air pressure may be applied with the same pulse width in synchronization with the voltage being applied to the electrode 1b as described above, but in reality, the air pressure is applied to the heating resistor after the voltage is applied to the electrode 1b. Generally, it takes several to ten years for the heat generated by the IC to be conducted to the ink and for the ink to dissolve. Therefore, pressure is applied at the same time as the voltage is applied to the electrode 1b, or after a little delay, and
It is preferable to adopt a configuration in which the pressure application is canceled a little later than the end of voltage application to the line.

Furthermore, if the pulse width of the pressure application is made somewhat larger than the pulse width of the voltage application to the electrode lb, the transfer of the ink onto the recording medium 2 can be ensured.

On the other hand, if the pressure application pulse width is made shorter than the voltage application pulse width, it is possible to improve ink depletion for each line.

Even when the pressure application pulse width is made to be different from the voltage application pulse width, as mentioned above, there is usually a delay in melting of the ink with respect to the application of voltage, so the application of pressure is started after the application of the voltage pulse is canceled. You may also do so.

Even more! If the line does not include a signal for applying a voltage to the electrode lb, that is, if it is a non-recording line, no pressure can be applied, so that erroneous transfer can be prevented and fogging etc. can be effectively prevented.

Incidentally, in the above-mentioned embodiment, a configuration using pneumatic pressure was shown as a means for applying pressure to the ink in the recording rad l, but the means is limited to the above-mentioned pneumatic pressure as long as it can uniformly apply pressure to the ink. Therefore, various other pressure applying means can be applied, such as a configuration in which a piezoelectric vibrator made of ceramic, polyvinylidene fluoride, etc. is arranged near the ink passage hole and pressure is applied by this.

Further, the recording head l is not limited to the above-mentioned fixed type, but may be configured as shown in FIG. A plurality of electrodes 1e, if are divided in a non-contact manner in the circumferential direction, a heat generating resistor 1g is provided between the electrodes 1e, if, and an ink passage hole 1h consisting of a through hole is provided at the position of the heat generating resistor 1g. (Japanese Patent Application No. 61-16747), therefore, the predetermined electrode 1e
.

When voltage is applied to 1r via brushes li and l'j,
The heating resistor 1g at the intersection of the electrodes 1e and If generates heat.

If the recording head l is configured as described above, the recording head l
rotates as the recording medium 2 moves, so the electrode 1 rotates as the recording medium 2 moves.
When ink oozes out from the matrix-formed ink passage holes 1h and transfer recording is performed by applying voltage to e and If and applying pressure to the ink, ink trailing and fogging can be more effectively prevented. It becomes possible to do so.

Furthermore, when a recording medium whose surface is laminated with a polymer film such as Teflon or polypropylene is used, images can be erased manually or automatically, allowing repeated recording.

<Effects of the Invention> The present invention, as described above, selectively heats ink stored in a container having ink passage holes to lower its viscosity, and
Since recording is performed by applying pressure in response to the heating, there is no need for ink ribbons, which are consumables like in conventional thermal transfer recording, and the recording is clear at high speed without ink trailing or fogging. It is possible to record images.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of a recording configuration according to an embodiment of the present invention, FIG. 2 is a perspective explanatory diagram of a recording head, FIG. 3 is an explanatory diagram of main parts of the recording head, and FIG. 4 is a rotary recording head. An explanatory diagram of
FIG. 5 is an explanatory diagram of the prior art. 1 is the recording head, la is the base, lb, le, 1f are electrodes, tc, tg are heating resistors, ld, lh are ink passage holes, li, lj are brushes, Ik is insulation! ! 2 is a recording medium, 3 is a connector, 4 is a signal cable, 5 is a power supply, 6 is a drive controller, 7 is a diffuse controller, 8 is a diffuse regulator, 9 is a pressure tube, 10 is a platen It's Laura.

Claims (2)

[Claims] (1) A container capable of storing ink inside is provided with a plurality of ink passing holes consisting of through holes, and a heat generating means for selectively heating the ink passing holes or the vicinity thereof is provided, and the heat generated by the heat generating means is provided. A recording head connected to pressure means for applying pressure into the container. (2) A container containing ink and having an ink passage hole consisting of a large number of through holes is brought into contact with a recording medium and moved relative to the recording medium, and selectively heats the ink passage hole or its vicinity. The ink near the ink passage hole is made to have a low viscosity, and pressure is applied to the ink in the container in correspondence with the heating cycle, so that the ink with the reduced viscosity is transferred from the ink passage hole to the recording medium. Recording method.