JPS5822742B2 - Electric power plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a far-infrared ray emitting element for electrophotographic fixing, and the present invention relates to a far-infrared ray emitting element for electrophotographic fixing. It relates to a material coated with far-infrared emitting material.

In general, electrophotography involves depositing (developing) a mixture of colored charged particle powder and polymer onto an electrostatic latent image formed on a photoconductor, and then the deposited charged particle powder and polymer. A method has been adopted in which a mixture of the above and the like is transferred onto a paper surface, the transferred polymer is dissolved by heating, and the colored charged particles are fixed (fixing).

Conventionally, the heating source for fixing this electrophotography has been a method of transferring heat from a heated roll to the transferred paper, a method of passing the transferred paper through a heated atmosphere, or a method of supplying thermal energy by heat radiation. ing.

However, the heating method using heating rolls has a simple mechanical structure, high mechanical strength, and can make the heat distribution relatively uniform, but on the other hand, the rise time is slow, the fall time is also slow, it takes time to fix, and failures occur. If the paper fails to stop, for example, there is a risk of it being ignited.

In addition, the method using a thermal atmosphere has the advantage of uniform heat conduction to the paper, but the thermal efficiency is low, and the rise time and
It has the disadvantage of slow fall time.

Furthermore, heat can be easily controlled using methods using thermal radiation;
It ignites when paper comes into contact with it, and the rise and fall are slow, causing problems with spectral distribution relative to polymers.

Therefore, the heat source for fixing electrophotography must match the spectral absorption wavelength range of the polymer and colored charged particles, must not be ignited in a short period of time even if the paper comes into contact with it, and must have a short rise time.
Short fall times and easy electrical adjustment are required.

Furthermore, as shown in Figure 2, due to the spectral absorption characteristics of polymers, far infrared rays with wavelengths of 3 to 4μ and 9 to 10μ are effective, and colored charged particles uniformly absorb far infrared rays with wavelengths of up to 20μ, making it possible to generate electrons. Wavelength 3 to 4μ for photo fixation
The inventor has confirmed that a heating source that emits far infrared rays of 9 to 10 microns is highly compatible.

From this point of view, conventional incandescent lamps and xenon lamps using quartz tubes and glass tubes emit almost no radiation with wavelengths of 3μ or more due to the spectral transmission characteristics of the glass, and are not suitable for fixing electrophotography. is not compatible; on the other hand, as a radiation source that emits far-infrared light with a wavelength of 3μ to 20μ, for example, a far-infrared radiation source made by coating a far-infrared emitting material such as ceramics on the surface of a metal heating element such as a sheathed heater. However, due to its large heat capacity, the rise time and fall time of infrared radiation are slow, and if the paper is stopped due to a malfunction, for example, there is a risk that the paper will burn even if the switch is turned off.

The present invention was invented in view of the above points, and involves coating a far-infrared emitting material on the surface of a transparent envelope in which a heating element is disposed, and reducing the tube wall load by 0.4w/i to 2w. /cril, which has good heating efficiency for polymers in electrophotographic fixing,
It also has excellent rise and fall characteristics, and has a surface temperature of 400℃.
To provide a far-infrared ray emitting element for electrophotographic fixing that has no risk of being burned even if paper is touched at temperatures below .degree.

Next, the structure of an embodiment of the present invention will be explained with reference to the drawings.

Reference numeral 1 denotes an outer envelope, which is made of a heat-resistant, light-transmitting, electrically insulating material such as quartz glass or high silicate glass, and is formed into an arbitrary shape, for example, an elongated tube shape.

A heating element 2 such as a tungsten filament is inserted into the center of the outer envelope 1 along the axial direction, and lead-in foils 4 such as molybdenum foil are connected to conductive wires 3 at both ends of the heating element 2. Further, the outer groove wires 5 connected to both the lead-in foils 4 respectively protrude outward from both ends of the outer envelope 1.

Further, a flat pinch seal portion 6 is formed around the two end introduction foil portions 4 of the outer envelope 1, and an inert gas or an inert gas and a halogen or a halogen compound are sealed inside the outer envelope 1, or It is formed in a vacuum.

Further, an electrically insulating tube 7 made of porcelain or the like is provided at both ends of the outer envelope 1, and a terminal 8 connected to the outer groove wire 5 is fitted into the electrically insulating tube 7.

Next, 9 is made of aluminum and a mixture of aluminum and ceramics, such as titanium oxide, which has high thermal conductivity, has a thermal expansion coefficient intermediate between that of the envelope 1 and the far-infrared emitting material described below, and has a high infrared emissivity. A base layer formed of a material with strong adhesiveness to the enclosure 1, which is adhered to the surface of the enclosure 1 by thermal spraying or the like, preferably leaving a pinch seal portion 6 encapsulating the introduction foil 4. There is.

This base layer 9 is used as necessary.

Next, reference numeral 10 denotes a far-infrared emitting material layer, which is formed on the surface of the base layer 9 by thermal spraying or the like.
Similarly to the base layer 9, the pinch seal portion 6 is also preferable.
form by leaving.

An example of this far-infrared emitting material is shown in Periodic Table 2 of the Elements.
A mixture of an oxide, carbide or nitride of one or more elements in the third period and an oxide, carbide or nitride of one or more elements in the fourth or fifth period, or a semiconductor oxide Materials based on titanium, ZrO2 and Si
Mainly O2, Fe, co.

A fired body of a substance to which oxides such as Ni, Cr, Mn and clay are added, a mixture of ZrO2 and TiO2, and 1
0% by weight or less of substances or AI 203 and S 10
A material consisting of SiO2 containing 8% by weight or less of the total amount of A1□03 and 8102 is suitable, and emits far infrared rays in a long wavelength range of 5 to 50μ.

As can be understood from the following explanation, the tube wall load of this far-infrared radiation element is 0.4 to 2.0w/C1? Must be L.

However, as a result of various experiments, 1.2 to 1.8 w/i
Particularly good results were obtained in the range of 1.5 w/C.
I? It was found that optimal results can be obtained near .

Next, the operation of this embodiment will be explained.

The surface salinity of the far-infrared radiation element during normal operation is 400°C.
Even if the paper onto which the polymer and the colored charged particle powder are transferred comes into contact with the far-infrared ray emitting element below, there is no risk of burning up.

In other words, according to the inventor's experiments, even if a thin piece of paper was placed at a distance of 1 crIL from the present far-infrared emitting element lit at a surface temperature of 400°C for 5 minutes, it did not burn, and the quartz glass did not burn. The halogen lamp used as the envelope will burn a little.

Furthermore, if paper is brought into contact with the present far-infrared radiation element and electricity is cut off at the same time, if the surface temperature is below 400°C, the paper will become somewhat hot but will not burn.

It has been confirmed that paper begins to burn when the surface humidity exceeds 450°C.

Furthermore, the relationship between the surface temperature of the present far-infrared radiating element and the tube wall load is as shown in Figure 3 according to the inventor's experiments, and in order to reduce the surface temperature to 400°C or less, the tube wall load is 2w/ Cl
It is clear that it is sufficient to make it less than l1.

Also, looking at the relationship between this tube wall load and the infrared radiation wavelength, as shown in Figure 4, the spectral radiation power distribution shifts to longer wavelengths when the tube wall load is lowered, and the tube wall load causes the surface temperature to reach 400°C. For 2w/crIL, the peak wavelength is 4μ.

Based on the spectral characteristics of the polymer, the critical wavelength is considered to be 10μ, and the tube wall load at a wavelength of 10μ is 0.4w/criL.
and the surface humidity is 80°C.

Also, is this tube wall load 0.4 to 2w/Cr? In the range of L, there was almost no difference in the rise and fall time characteristics of far-infrared radiation, and in particular, the fall times were almost the same.

However, the rise time of far-infrared radiation was set as the time required for the radiation output to reach 90% of the saturation value after energization at room temperature, and the fall time was set as the time required for the radiation output to drop to 20% after energization was cut off.

And with this far-infrared radiating element, the rise time is 1 minute and 30 minutes.
The conventional sheathed heater had a rise time of 15 minutes and a fall time of 30 minutes.

In the above embodiment, an infrared lamp using a tungsten filament with pinch seals formed at both ends was described, but it may also be an outer shell of a one-eye terminal in which the pinch seals are formed only at one end. The shape is not limited to an elongated tubular shape, but may be any suitable shape such as a spherical shape or a plate shape.

Furthermore, there is no need to enclose an inert gas such as halogen in the envelope 1 or create a vacuum.

Further, the base layer 9 of the far-infrared emitting material layer 10 is not necessarily required.

According to the present invention, since the tube wall load of the far-infrared radiating element in which the far-infrared ray emitting material layer is formed on the surface of the outer envelope in which the heating element is disposed inside is set to 0.4 to 2 w/ffl, electrophotography When fixing the colored charged particle powder and polymer onto the transferred paper, far-infrared radiation matching the spectral absorption characteristics of the polymer and the spectral absorption characteristics of the colored charged particles can be obtained, allowing for efficient heating and fixing. Moreover, the rise time and fall time of far infrared radiation are short, making it economical. In addition, if the paper stops due to a malfunction, the humidity will drop immediately after the power is cut off, and the paper will not be burned. The temperature is also maintained below 400°C, and even if the paper comes into contact with the far-infrared radiation element, there is no risk of it being burned, increasing safety.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view of a far-infrared ray emitting element showing an embodiment of the present invention, Fig. 2 is a graph of spectral absorption characteristics of a polymer for toner in electrophotography, and Fig. 3 is a diagram of a far-infrared ray emitting element. FIG. 4 is a graph showing the relationship between tube wall load and humidity difference, and FIG. 4 is a graph showing the relationship between far-infrared radiation peak wavelength and tube wall load. 1... Outer envelope, 2... Heating element, 10... Far-infrared emitting material.

Claims (1)

[Claims] 1 Consists of a heating element, an electrically insulating envelope that is disposed outside the heating element and has translucency, and a far-infrared emitting material formed on the surface of the envelope, reducing the load on the tube wall to 0. A far-infrared radiating element for electrophotographic fixing, characterized in that it has a radiation density of 4 to 2 W/cri.