JPS62130863A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To perform favorable ink jet recording irrespective of the quality of a paper used, by providing a plate form fixed platen on the front side of an ink jet recording head, and heating the platen by a heat generating element provided on the back side of the platen to preheat and heat the back side of a recording paper, thereby drying a recording ink. CONSTITUTION:A recording paper 3 is brought into sliding contact with a fixed platen 1 heated by a heat generating element 12, whereby the paper 3 is preheated and heated before, during and after ink jet recording through contact heat transfer, and a recording ink adhered to the paper by the ink jet recording is rapidly dried, so that a favorable printed condition can be obtained through preventing undesired blurring, wrinkling of the paper or contamination with an unfixed ink from occurring. A paper bail 7 prevent the recording paper 3 from being levitated, and brings the paper 3 into close contact with the fixed platen 1, thereby enhancing a heat transfer effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording apparatus having a means for heating and drying recording ink.

[Prior Art] A representative example of an inkjet recording apparatus having a means for heating and drying recording ink is disclosed in Japanese Patent Application Laid-open No. 55-69464 and 55.
-84670, which heats the entire platen with a heating element installed inside the platen to heat the recording paper from the back side, drying the recording ink and eliminating unnecessary bleeding and paper wrinkles.
This is an extremely effective means for preventing stains caused by unfixed ink.

[Problems to be Solved by the Invention] However, in the conventional example, a heating element is formed inside the platen to heat the entire platen, so there are the following problems.

First, considering thermal efficiency, the smaller the total volume of the platen, the faster it can be warmed up with less heat, but in the conventional example mentioned above, the entire platen is heated from inside, so even the parts that do not come into contact with the recording paper are heated. This cannot be said to be an efficient heating method.

Furthermore, in the case where a heating element is provided in a hollow platen and the platen is heated by radiant heat, the heat efficiency is further deteriorated because the heat is passed through an air layer with extremely poor heat conduction.

As described above, the conventional example requires a wasteful amount of heat to heat the platen, and has disadvantages in that heating takes time and requires large power consumption.

[Means for Solving the Problems] The inkjet recording apparatus of the present invention has a plate-shaped fixed platen on the front surface of the inkjet recording head, and a heating element is provided on the back surface of the platen that does not face the recording head. By heating the recording paper, the back side of the recording paper is preheated and heated before and after inkjet recording to dry the recording ink.Furthermore, a temperature sensor is provided to detect the temperature of the recording paper or the heating element. The temperature of the heating element is controlled by a signal from a temperature sensor, or the heating element itself performs its own temperature control to maintain the preheating/heating temperature of the recording paper at a constant temperature.

[Function] According to the present invention, since the platen that requires heating is only the size of the heating and drying portion of the recording ink, warm-up can be completed in a shorter time and with less electric power than in the past. Power consumption during use can also be lower than conventional heating from inside the platen.

[Embodiment] FIG. 1 is a schematic overall configuration diagram showing an embodiment of an inkjet recording apparatus of the present invention.

The recording head 5 moves in the direction of an arrow r while being guided by a carriage guide 6, and performs inkjet recording on the recording paper 3, which is fed by intermittent line feeds in synchronization with the recording head 5 by the paper feed roller 2 and the guide roller 4. The recording head 5 is provided with a plurality of ink ejection ports 13 as shown in FIG. 3, which is a partial side view of FIG. It is formed on top. The recording head 5 of this example has nine ink ejection ports in a vertical row with a pitch of 0.635 mm, and ejects ink droplets with a diameter of about 120 pm.

The ink material used is an aqueous ink whose main components are 10 to 20% glycerin and 1 to 2% dye dissolved in water.

The fixed platen 1 is suitably made of a material with good thermal diffusion, such as an aluminum alloy or a thermally conductive plastic material, and in this example, an aluminum alloy plate with an average thickness of 1 mm and a size of about 250 mm x 30 mm is used. Recording head 5 on fixed platen 1
As shown in FIG. 2, a heating element 12 is provided on the back surface not facing the . FIG. 2a shows an example in which a POSISTOR is used as the heating element 12, and five POSISTORs each having a rated voltage of 30V and an average resistance value of 22Ω are arranged in a brown color or the like. Figure 2 shows an example in which a nichrome wire is used for the heating element 12, and an insulating material 13 is provided between it and the fixed platen 1.
A 100V 250W nichrome wire is used.

In FIG. 3, the recording paper 3 is in sliding contact with the fixed platen 1 heated by the heating element 12, and is preheated and heated by contact heat transfer before and after inkjet recording, rapidly drying the recording ink recorded by the inkjet recording. To obtain good printing quality by preventing unnecessary bleeding, paper wrinkles, and stains caused by unfixed ink. The paper presser 7 prevents the recording paper 3 from floating, and also makes the recording paper 3 tightly attached to the fixed platen 1 to enhance the heat conduction effect.

The recording paper heating temperature can be controlled to maintain a constant temperature using the following two methods depending on the type of heating element 12.

First, in the case where the heating element 12 itself does not have a self-temperature control function, such as the nichrome wire shown in Figure 2, as shown in Figure 3,
The surface temperature of the recording paper 3 or the fixed platen 1 is detected by a temperature sensor 14, and the power supplied to the heating element power source 15 is controlled based on this detection signal to maintain the recording paper heating temperature at a constant temperature. In addition, if the heating element 12 itself has a self-temperature control function, such as the POSISTOR shown in FIG. The recording paper heating temperature is maintained at a constant temperature.

In this example, when inkjet recording was performed using various commercially available high-quality papers of different sizes as the recording paper at a heating temperature of 100 to 130°C, good image recording was achieved regardless of the paper quality, and the recording ink dried sufficiently. There were no paper wrinkles or stains caused by unsettled ink.The power consumption was also low for 30 seconds during warm-up in both cases of the heating element shown in Figure 2 a and b.
The power consumption is 50v1, and the average power consumption during use is 30W, which is equivalent to the power consumption of a wing when the same performance is achieved using the conventional method.

Commercially available high-quality paper may tend to curl on the heating surface side depending on the heating temperature and +ff+ C-j' R dimensions.
l! I'! It is desirable to feed the recording paper as linearly as possible after preheating.
It is similar to the figure.

Further, although this example is a monochrome inkjet recording apparatus, it is obvious that the present invention can also be applied to a color inkjet recording apparatus.

[Effects of the Invention] As described above, the inkjet recording apparatus 1 of the present invention
According to t, it is possible to warm up the device in a shorter time and with less power than before, reducing the average power consumption!
Good inkjet recording can be achieved on general-purpose recording media such as commercially available high-quality paper, regardless of the paper quality, using the conventional 2-Iso method.

[Brief explanation of drawings]

FIG. 1 is a schematic overall configuration diagram showing an embodiment of an inkjet recording apparatus of the present invention. FIG. 2 is a perspective view showing how the heating element is installed. FIG. 3 is a partial side view of FIG. 1. 4th page is a partial J+I side view showing another embodiment of the present invention. 4...Guide roller 6...Carriage guide 8...Paper feed gear and above Fig. 3 Fig. 4

Claims (2)

[Claims] (1) A plate-shaped fixed platen is provided on the front side of the inkjet recording head, and a heating element is provided on the back side of the platen that does not face the recording head to heat the platen, so that the back side of the recording paper is heated before and after inkjet recording. An inkjet recording device that dries recording ink by preheating and heating. (2) By providing a temperature sensor that detects the temperature of the recording paper or the heating element and controlling the temperature of the heating element based on a signal from the temperature sensor, or by controlling the temperature of the heating element itself, The inkjet recording apparatus according to claim 1, which has a function of keeping the recording paper preheating/heating temperature constant.