JPS63260447A - Phase change ink jet device - Google Patents

Abstract

PURPOSE:To smoothly supply ink to an ink injection unit by filtering liquid ink by a heating filter to efficiently removing impurities, such as dusts contained in the ink. CONSTITUTION:An ink reservoir 11 is connected through an ink supply unit 14 to an ink injection unit, and so disposed as to heat the whole device from the reservoir 11 to the unit from the bottom. A heating filter 13 is formed of ceramics, heated by a current, disposed at a predetermined position in the reservoir 11, and controlled in heating by a temperature control 15. The filter 13 operates to perform both the roles of phase change means for melting the solid hot melt ink and a filter, and solid hot melt ink 100 supplied on the filter 13 is directly heated, melted and filtered by the filter 13 to flow into the reservoir 11.

Description

[Detailed Description of the Invention] [Summary] The present invention provides a phase change ink ejecting device that effectively removes impurities such as dust and dust contained in the ink to smoothly supply ink to the ink ejecting section. This purpose is achieved by filtering liquid ink using a heating filter.

[Industrial application field]

The present invention relates to improvements in phase change ink ejection devices.

In ink jetting devices that use conventional liquid ink,
Clogging occurs due to ink drying on the nozzle surface, which impedes stable operation and makes maintenance difficult.

On the other hand, recently some phase-change inks (hot-melt inks) have been used, which are solid at room temperature but melt when heated to a jettable viscosity. Clogging is eliminated, and it is possible to achieve highly reliable jetting characteristics and high-quality recording characteristics on various types of recording paper.

On the other hand, with this hot melt ink, the longer it is heated for a long time or at a high temperature, the more the ink deteriorates due to oxidation, etc., so the phase change of the ink and the supply of ink to the ink jetting part must be achieved quickly and with appropriate heating. Inevitably, speeding up ink supply leads to stable ink jetting, stabilization of jetting, and shortening of jetting cycles, making highly reliable high-speed printing possible.

Further, in an ink ejecting device, in order to stabilize and increase the reliability of ejection, impurities such as dust and dirt contained in the ink must be removed, and a filter is used for this purpose.

[Conventional technology]

FIG. 3 is an explanatory diagram of the main part structure of a conventional phase change ink ejecting device, in which 1 is an ink reservoir, 2 is a heater, and 3 is a filter. Solid true melt ink (solid phase change ink) 100 is supplied onto the inclined plate 4 at the inlet of the ink reservoir 1 . This inclined plate 4 and the heater 2 extending below it constitute a phase change means 5, and the inclined plate 4 is heated by the heater 2 to a temperature higher than the melting point of the true melt ink 100. . Thereupon, the supplied solid real melt ink 100 melts and becomes liquid ink, flows down on the inclined plate 4, is filtered by the filter 3, and accumulates in the ink reservoir 1. The liquid ink 100' in the ink reservoir passes through the ink supply path 6 and reaches an ink ejecting section (not shown), and is ejected from a nozzle by actuating a piezoelectric element of the ink ejecting section at a predetermined time.

Although FIG. 3 shows an example in which the filter 3 is immersed in the liquid ink 100' of the ink reservoir 1,
The filter may be provided anywhere in the ink supply system from the phase change means 5 to the ink jetting section. However, if the filter is provided exposed above the liquid ink 100' of the ink reservoir 1, the effective filtration area will be small. It has the disadvantage of becoming.

[Problem that the invention seeks to solve]

In the conventional ink ejecting apparatus having such a configuration and operation, it takes a certain amount of time for the liquid ink to pass through the filter and be filtered, which has caused a problem in terms of responsiveness.

This can be solved by making the area of the filter sufficiently large, but this is not a good idea because it leads to an increase in the size of the device.

[Means for solving problems]

The present invention provides an ink ejecting device capable of solving the above-mentioned problems, and as means for that purpose, the present invention includes a phase change means for melting the supplied solid phase change ink, and a phase change means for melting the supplied solid phase change ink. an ink ejecting section that receives a supply of liquid ink melted by the ink and operates at a predetermined time to eject the liquid ink, and a filter is provided in the ink supply system from the phase change means to the ink ejection. In the injection device, a heating filter is used as the filter.

This heating filter can be used as a phase change means by having the function of melting solid phase change ink.

Further, the heating filter can also be provided with a temperature control mechanism.

[Effect]

When a heating filter is placed immersed in liquid ink, the heating by the heating filter quickly reduces the viscosity of the nearby liquid ink, which improves filtration efficiency as the entire surface of the filter contributes to filtration. The response is also faster.

Also, when using a heating filter as a phase change means,
Since the ink is melted and filtered at the same time, the response is faster. By effectively utilizing the large surface of the heating filter, the efficiency of melting and filtration can be improved.

In either case, ink deterioration can be reduced by increasing the filter heating temperature only when ink is supplied, and lowering the heating temperature or stopping heating when ink is not supplied.

〔Example〕

The present invention will now be described in detail with reference to FIGS. 1 and 2.

A first embodiment is shown in FIG.

FIG. 1 is an explanatory diagram of the main part structure of a phase change ink ejecting device according to the present invention. In the figure, 11 is an ink reservoir, 12 is a heater, and 13 is a heating filter. The ink reservoir 11 is
It communicates with an ink ejecting section (not shown) via an ink supply path 14, and the heater 12 is arranged to heat the entire apparatus from the ink reservoir 11 to the ink ejecting section from the bottom.

The heating filter 13 is made of ceramic or the like and is heated by an electric current.
It is placed at a predetermined position in the interior as shown in the figure, and its heating is controlled by a temperature controller 15.

The heating filter 13 serves both as a phase change means for melting the solid hot melt ink and as a filter, and the solid hot melt ink 100 is supplied onto the heating filter 13 . The supplied solid real-melt ink 100 is directly heated, melted, and filtered by the heating filter 13, and flows into the ink reservoir 11. In this case, melting and filtration of the ink are performed simultaneously, resulting in faster response. If the wide surface of the heating filter 13 is effectively utilized, the efficiency of melting and filtration can be improved, which is even more effective. The liquid ink 100' that has flowed into the ink reservoir 11 is maintained at a constant temperature by heating by the heater 12, and is supplied to the ink ejecting section through the ink supply path 14 as necessary. The amount of ink supplied to the ink supply path 14 can be controlled by a temperature controller 15 for heating control of the heating filter 13.

FIG. 2 shows a second embodiment.

FIG. 2 is an explanatory diagram of the main part structure of another phase change ink ejecting device according to the present invention, in which 21 is an ink reservoir and 22 is a heating filter. The ink reservoir 21 is connected to an ink ejecting section (not shown) via an ink supply path 23, and the heating filter 22 is made of ceramic or the like and is heated by electric current. 24 is heating filter 2
This is a temperature controller that controls the temperature of No. 2.

In this example, a heater for heating the ink reservoir 21 is not provided, and the heating filter 22 is used to heat the liquid ink 10.
0' and serves to maintain the liquid ink 100' at a constant temperature.

In this case, the heating by the heating filter 22 that is in direct contact with the liquid ink 100' quickly reduces the viscosity of the liquid ink in the vicinity, so the entire surface of the filter contributes to filtration, which improves filtration efficiency. The responsiveness also becomes faster, but the degree of response can be controlled by controlling the temperature of the heating filter 22 by the temperature controller 24. However, in order to reduce deterioration of the liquid ink 100', it is necessary to prevent the heating temperature of the heating filter from becoming too high.

The ink supplied to the ink reservoir may be a solid phase change ink 100 as shown in FIG. 2, but may also be a liquid ink that has been liquefied in advance by a phase change means.
Although FIG. 2 shows an example in which the heating filter 22 is provided within the ink reservoir 21, the heating filter may be installed at any position from the phase change means to the ink jetting.

In the above explanation, a heating filter that generates heat by itself is illustrated, but the heating filter may also be configured to include a heating means and a non-heat generating filter that is thermally connected to the heating means. As the filter medium in this case, it is effective to use a metal such as stainless steel, which has good thermal conductivity and is resistant to deterioration.

〔Effect of the invention〕

As described above, according to the present invention, by employing a heating filter, it is possible to improve the filtration efficiency and smoothly supply ink to the ink jetting section.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the main part structure of a phase change ink ejection device according to the first embodiment of the present invention, FIG. 2 is an explanatory diagram of the main part structure of the phase change ink ejection device according to the second embodiment of the present invention, FIG. 3 is an explanatory diagram of the structure of the main parts of a conventional phase change ink ejecting device. In the figure, 11.21 is an ink reservoir, 13.22 is a heating filter, 14.23 is an ink supply path, and 15.24 is a temperature controller. , 100 is solid true melt ink (solid phase change ink)
, 100' is liquid ink.

Claims (1)

[Claims] 1. Phase change means for melting supplied solid phase change ink, and receiving the supply of liquid ink melted by the phase change means and operating at a predetermined time to eject the liquid ink. An ink ejecting device comprising an ink ejecting section, and a filter for filtering liquid ink is provided in an ink supply system from the phase change means to the ink ejecting section, characterized in that a heating filter is used as the filter. Phase change ink ejector. 2. The phase change ink ejecting device according to claim 1, wherein the heating filter also serves as the phase change means. 3. The phase change ink ejecting device according to claim 1 or 2, wherein the heating filter is provided with a temperature control function.