JPH07186434A - Recording device - Google Patents

Abstract

PURPOSE:To provide a recording device, with which high quality recording is realized, by a method wherein unnecessary ink is prevented from spreading. CONSTITUTION:By providing an ink repellent part, at which ink repelling treatment for repelling ink or electrically viscous fluid is applied, at and near the portion contacting with the matter to be recorded 8 so as to repel the ink discharged from a nozzle 4, resulting in preventing unnecessary spread of ink such as the entering of ink into the contacting portion between the recording head and the matter to be recorded 8 from developing and realizing high quality recording.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct recording type recording apparatus using an electrorheological fluid as ink.

[0002]

2. Description of the Related Art JP-A-4-257485 discloses a direct recording method using an electrorheological fluid as ink. This is because the ink ejection port is brought into contact with the recording medium, static pressure is applied to the ink in the direction toward the recording medium, and the application of the electric field to the ink in the nozzle is stopped, so that the ink is directly ejected without flying. It is to be attached to a recording medium. According to this method, the pressure applied to the ink can be lowered as compared with the ink jet method, and recording can be performed with a simple head configuration, so that it is possible to provide a smaller-sized recording apparatus at lower cost.

[0003]

However, since the ink using the electrorheological fluid has a slow permeation rate into the recording medium, in the above-mentioned conventional one, as shown in FIG. A part of the ink spreads between the head members 52 and 53 and the recording medium 54, and the ink is likely to have a trailing shape, which is a cause of deterioration in recording quality.

It is an object of the present invention to provide a recording apparatus capable of performing high quality recording without ink entering between the recording head and the recording medium.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a recording apparatus in which an electrorheological fluid is used as ink and is directly attached to a recording medium without causing the ink to fly. The above problem is solved by applying an ink-repellent process that repels the ink in the vicinity thereof.

Further, using an electrorheological fluid as ink,
In a recording apparatus that directly adheres to a recording medium without causing the ink to fly, an ink repellent member that repels the ink is provided near an ink ejection port, and recording is performed with the ink repellent member and the recording medium being in contact with each other. This solves the above problem.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a recording head of a recording apparatus according to the present invention. In the figure, 1 is a first head member,
Reference numeral 2 denotes a second head member, which forms an ink chamber 3 filled with ink which is an electrorheological fluid, and a nozzle 4 for ejecting ink in the ink chamber 3.
The ink is applied with a static pressure of about 0.01 to 1 kgf / cm @ 2 in the direction of arrow A. Reference numeral 5 is a common electrode provided in common to each nozzle, and 6 is an individual electrode provided individually for each nozzle. Reference numeral 7 denotes an ink-repellent portion that has been subjected to an ink-repellent treatment that repels ink, and this treatment is applied to the nozzle 4, the contact portion between the recording head and the recording medium, and its vicinity. Reference numeral 8 denotes a recording medium, which is sent in the direction of arrow B. 9 is a platen.

The first head member 1 and the second head member 2 are made of plastic, glass, ceramics, metal or the like.

The common electrode 5 and the individual electrode 6 have a thickness of 0.
Metal materials such as Cr, Al, Ni, etc. with an IT of 1 to 5 μm
It is formed of a conductive material such as O by a thin film forming method such as sputtering or vapor deposition, or a means such as printing. In order to protect the electrodes, an inorganic insulating film such as SiO2 or SiN or an organic insulating film such as polyimide may be provided on the electrode metal in a thickness of about 0.1 to 20 .mu.m.

The ink-repellent process is performed by plasma-polymerizing a resin such as fluorine-containing ethylene such as tetrafluoroethylene or trifluoroethylene or fluorine-containing propylene such as hexafluoropropylene to a thickness of 0.1 to 5 by plasma polymerization.
It is formed to about μm. For example, C2 F4 as a monomer
With a monomer flow rate of 20 ml / min and vacuum degree of 0.1
torr, discharge output 50w, time 12 minutes, distance between electrodes 3
0 mm, electrode area φ290 mm, thickness 0.6 μm
The ink repellent portion 7 is formed.

The ink repellent treatment may be carried out by diluting a fluororesin or a silicone resin with an organic solvent such as trichlene, forming a coating film by a spray coat method or a dipping method, and then heating and curing the film.

The first head member 1 is formed so that a gap of several μm to several tens of μm is formed between the first head member 1 and the recording medium 8 during recording.

FIG. 2 shows a state in which the first head member and the second head member of the recording head are separated. In the figure, the same reference numerals as those in FIG. 1 indicate the same elements. A plurality of nozzles 4 to 4 are formed on the second head member 2. The ink ejection port of the nozzle 4 is a quadrangle having a side length of about 30 to 200 μm.

The electrorheological fluid as ink is prepared by dispersing colorants such as pigments and dyes and solid fine particles such as water-containing polymer fine particles and ceramic fine particles in an electrically insulating liquid such as mineral oil, hydrocarbon liquid or sicone oil. If desired, additives may be added for the purpose of adjusting viscosity, preventing oxidation, maintaining dispersibility, and the like.

In the recording head having the above structure,
An electric field is selectively applied to the ink in the nozzle 4 by the common electrode 5 and the individual electrode 6 to change the viscosity of the ink, thereby controlling the adhesion from the nozzle 4 to the recording medium 8.

When the common electrode 5 and the individual electrode 6 are set to the same voltage, the electric field is not applied to the ink and the viscosity of the ink is low. Therefore, the static pressure causes the ink to be ejected from the nozzle 4 to the recording medium 8. Recording is carried out by attaching. FIG. 3 shows how the ink adheres to the recording medium 8. In the figure, the same reference numerals as those in FIG. 1 indicate the same elements. Since the ejected ink is repelled by the ink repellent portion 7, it quickly separates from the recording head and permeates the recording medium 8. Further, since there is a gap between the first head member 1 and the recording medium 8, the ink that has started to permeate the recording medium 8 is not sufficiently absorbed by the recording medium 8. Further, there is no further contact with the first head member 1, and the first head member 1 does not cause the ink to have a trailing recording shape. On the other hand, the second head member 2 is in contact with the recording medium 8, but since the ink repellent portion 7 has been subjected to the ink repellent treatment, the ink is repelled, and the ink is ejected from the second head member 2 and the recording medium. The second head member 2 does not enter the contact portion with 8 and the ink does not have a recording shape with a trailing tail.

On the other hand, when an electric field is applied between the common electrode 5 and the individual electrode 6, the viscosity of the ink increases and the ejection of the ink from the nozzle 4 is stopped. Not done. At this time, the voltage applied between the electrodes is about 10 to 200 v.

As described above, high quality recording can be performed without the ink spreading unnecessarily.

In the above embodiment, the ink repellent portion 7 is formed by directly subjecting the first head member 1 and the second head member 2 to the ink repellent process, but FIGS. 4 (a) and 4 (b). As described above, the ink repellent member 41 that has been subjected to the ink repellent treatment may be attached near the ink ejection port, and the ink repellent member 41 and the recording medium may be brought into contact with each other for recording.

[0021]

According to the present invention, since the ink-repellent process for repelling ink is applied to the ink ejection port and its vicinity, it is possible to prevent the expelled ink from unnecessarily spreading.
You can make high quality records.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration example of a recording head of a recording apparatus according to the present invention.

FIG. 3 is an explanatory diagram for explaining a recording operation of the recording apparatus according to the present invention.

FIG. 4 is an explanatory view showing another embodiment of the present invention.

FIG. 5 is an explanatory view showing a conventional example.

[Explanation of symbols]

 7 Ink repellent part 41 Ink repellent member

Claims (2)

[Claims] 1. A recording apparatus in which an electrorheological fluid is used as ink and is directly attached to a recording medium without causing the ink to fly, and the ink is repelled at a portion of the ink discharge port that contacts the recording medium and in the vicinity thereof. A recording device characterized by being subjected to ink repellent processing. 2. An ink repellent member that repels the ink is provided in the vicinity of an ink ejection port in a recording apparatus that uses an electrorheological fluid as ink and directly adheres to a recording medium without causing the ink to fly. A recording apparatus, which performs recording while being in contact with a recording medium.