JP2004050695A - Optical fixing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce component costs and to fully secure an installation space of other components. <P>SOLUTION: A lamp unit 24 for yellow which consists of two fixing lamps 21 for yellow and a reflector 23, and a lamp unit 25 for magenta which consists of two fixing lamps 22 for magenta and a reflector 23 are set. One illuminance sensor 28 for detecting an irradiation amount of ultraviolet rays irradiated from each fixing lamp is set at the opposite side to fixing lamps via the reflector 23. A lighting hole 29 is set to the reflector 23 for making equally mixed the irradiation amount of ultraviolet rays irradiated from two lamps to the illuminance sensor 28. The irradiation amount of ultraviolet rays to a recording paper 10 is measured from a detected value of the illuminance sensor 28, based on which the irradiation amount of ultraviolet rays is adjusted to be an optimum value. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical fixing device that detects an irradiation amount of ultraviolet rays emitted from a fixing lamp and adjusts the irradiation amount to an optimum value.
[0002]
[Prior art]
There is known a color thermal printer that forms a color image by performing thermal recording on a color thermal recording paper provided with a yellow, magenta, and cyan thermal coloring layer. In a color thermal printer, in order to prevent the yellow and magenta thermal color developing layers from re-coloring after thermal recording, the color thermal recording paper after thermal recording is irradiated with electromagnetic radiation peculiar to each thermal color developing layer, for example, ultraviolet rays. Light fixing is applied.
[0003]
The light fixing device includes a yellow fixing lamp that irradiates near-ultraviolet rays having an emission peak of 420 nm to light-fix the yellow thermosensitive coloring layer, and a magenta lamp that irradiates ultraviolet rays having an emission peak of 365 nm to photofix the magenta thermosensitive coloring layer. The fixing lamp and a reflection plate provided behind these fixing lamps and reflecting the emitted ultraviolet rays toward the color thermal recording paper.
[0004]
If the light fixing is insufficient, the heat-sensitive coloring layer with poor fixing color develops at the time of thermal recording on the next heat-sensitive coloring layer, and the color balance of the printed image is lost. For this reason, the light fixing device is provided with an illuminance sensor for detecting the illuminance of the emitted ultraviolet light, and the amount of ultraviolet light applied to the color thermal recording paper is measured based on the detected value of the illuminance sensor. The amount of UV irradiation is adjusted to the optimum value.
[0005]
[Problems to be solved by the invention]
Some optical fixing devices include a plurality of, for example, two fixing lamps in order to shorten the fixing time. In the case of such an optical fixing device, it is necessary to prepare illuminance sensors for the number of fixing lamps. For this reason, there existed a problem that component cost increased and it was difficult to ensure the installation space of another component. In addition, since the illuminance sensor has a variation in measurement sensitivity for each product, there is a problem that a measurement error due to multiple use occurs.
[0006]
An object of the present invention is to provide a light fixing device capable of reducing the cost of components and sufficiently securing an installation space for other components.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is arranged in parallel in the transport direction of a color thermosensitive recording paper in which a yellow thermosensitive coloring layer, a magenta thermosensitive coloring layer, and a cyan thermosensitive coloring layer are layered in a surface sequence on a support. A yellow fixing lamp and a magenta fixing lamp for performing light fixing on the yellow thermosensitive coloring layer and the magenta thermosensitive coloring layer after thermal recording by irradiating ultraviolet rays having a specific wavelength range, and sandwiching these fixing lamps, In a light fixing device which is disposed on the opposite side of the color thermal recording paper and which comprises a reflecting plate for reflecting the ultraviolet rays toward the color thermal recording paper, a yellow lamp comprising two yellow fixing lamps and a reflecting plate A magenta lamp unit comprising a unit, two magenta fixing lamps and a reflector, and the opposite side of the fixing lamp across the reflector One illuminance sensor provided to detect the amount of ultraviolet light emitted from each fixing lamp, and the same amount of ultraviolet light emitted from the two lamps to the illuminance sensor provided on the reflector. And a daylighting hole.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram showing the configuration of a color thermal printer embodying the present invention. In the color thermal printer 2, a long color thermal recording paper (hereinafter simply referred to as recording paper) 10 is used as a recording medium. The recording paper 10 is set in the color thermal printer 2 in the form of a recording paper roll 11 wound in a roll shape. The recording paper roll 11 is rotated by a paper feed roller 12 in contact with the outer periphery, whereby the recording paper 10 is fed out and rewound.
[0009]
In the vicinity of the recording paper roll 11, a pair of conveying rollers 13 that sandwich and convey the recording paper 10 is disposed. The conveyance roller pair 13 includes a capstan roller 15 that is rotationally driven by a conveyance motor 14 and a pinch roller 16 that is in pressure contact with the capstan roller 15, and the recording paper 10 has a fixing direction A and a printing direction B. To reciprocate.
[0010]
As shown in FIG. 2, the recording paper 10 includes a support 41 and a cyan thermosensitive coloring layer 42, a magenta thermosensitive coloring layer 43, and a yellow thermosensitive coloring layer 44 that are sequentially formed. The yellow thermosensitive coloring layer 44 which is the uppermost layer has the highest thermal sensitivity and develops yellow with a small amount of heat energy. The cyan thermosensitive coloring layer 42 as the lowermost layer has the lowest thermal sensitivity and develops cyan with a large amount of thermal energy. The yellow thermosensitive coloring layer 44 loses its coloring ability when irradiated with near ultraviolet rays of 420 nm. The magenta thermosensitive coloring layer 43 develops magenta with intermediate thermal energy between the yellow thermosensitive coloring layer 44 and the cyan thermosensitive coloring layer 42 and loses the coloring ability when irradiated with 365 nm ultraviolet rays.
[0011]
In FIG. 1, a thermal head 17 and a platen roller 18 are arranged on the downstream side in the fixing direction A of the conveyance roller pair 13 so as to sandwich the conveyance path of the recording paper 10. On the surface of the thermal head 17 facing the recording paper 10, a heating element array 19 is provided in which a number of heating elements are formed in a line shape in a direction orthogonal to the conveyance direction of the recording paper 10. The platen roller 18 is disposed below the conveyance path at a position facing the heating element array 19. The platen roller 18 is movable in the vertical direction and is urged in a direction in which it is pressed against the thermal head 17 by a spring (not shown).
[0012]
The thermal head 17 is in pressure contact with the recording paper 10 conveyed in the printing direction B by the conveying roller pair 13 and heats the heating element array 19 to a predetermined temperature to cause each of the heat-sensitive coloring layers 42 to 44 to color. The platen roller 18 is driven and rotated in accordance with the conveyance of the recording paper 10 to facilitate the sliding contact between the recording paper 10 and the heating element.
[0013]
Two yellow fixing lamps 21 and two magenta fixing lamps 22 constituting the optical fixing device 20 are arranged downstream of the thermal head 17 in the fixing direction A. The yellow fixing lamp 21 emits near ultraviolet rays having an emission peak of 420 nm, and fixes the yellow thermosensitive coloring layer 44 of the recording paper 10. The magenta fixing lamp 22 emits 365 nm ultraviolet light to fix the magenta thermosensitive coloring layer 43. Behind the yellow fixing lamp 21 and the magenta fixing lamp 22 is provided a reflector 23 that reflects the emitted ultraviolet light toward the recording paper 10. The two yellow fixing lamps 21 and the reflector 23 constitute a yellow lamp unit 24, and the two magenta fixing lamps 22 and the reflector 23 constitute a magenta lamp unit 25.
[0014]
The reflector 23 is attached to the lamp base 26. The lamp base 26 is made of a sheet metal such as aluminum, and a circuit board 27 is attached to the back surface thereof. An illuminance sensor 28 is installed on the circuit board 27. The illuminance sensor 28 can detect the irradiation amount of ultraviolet rays emitted from the fixing lamps 21 and 22. The color thermal printer 2 measures the amount of ultraviolet light applied to the recording paper 10 from the detection value of the illuminance sensor 28, and adjusts the amount of ultraviolet light irradiated to an optimum value based on the measured amount.
[0015]
As shown in FIGS. 3 and 4, the illuminance sensor 28 is arranged between the fixing lamps 21 and 22, and can accurately detect the illuminance of each. The reflector 23 and the lamp base 26 are provided with a daylighting hole 29. The daylighting holes 29 are arranged such that the irradiation amounts of ultraviolet rays (indicated by a one-dot chain line and a two-dot chain line in FIG. 3) irradiated from the two lamps to the illuminance sensor 28 are the same. In this way, the illuminance of a total of four fixing lamps can be accurately detected by one illuminance sensor. In FIG. 3, in order to avoid complication, the irradiation amount of ultraviolet rays irradiated from the magenta fixing lamp 22 to the illuminance sensor 28 is omitted. In FIG. 4, the lamp base 26 and the circuit board 27 are omitted.
[0016]
In FIG. 1, a cutter 30 for cutting the long recording paper 10 for each recording area is provided on the downstream side of the fixing direction A of the yellow fixing lamp 21. A paper discharge port 31 for discharging the cut sheet-like recording paper 10 is provided on the downstream side of the cutter 30.
[0017]
Next, the effect | action by the said embodiment is demonstrated. When a print instruction is issued, the recording paper 10 is fed by the paper feed roller 12 and conveyed in the fixing direction A by the conveyance roller pair 13. Next, the recording paper 10 is conveyed in the printing direction B by reversing the conveying roller pair 13. During this conveyance, a yellow image is thermally recorded on the yellow thermosensitive coloring layer 44 by the thermal head 17. After the yellow image is thermally recorded, the yellow fixing lamp 21 is turned on while the recording paper 10 is conveyed in the fixing direction A, and the recording paper 10 is irradiated with near ultraviolet rays having a light emission peak near 420 nm emitted from the yellow image. The yellow thermosensitive coloring layer 44 is light-fixed. Similarly, after thermal recording of a magenta image by the thermal head 17 is performed on the magenta thermosensitive coloring layer 43, the recording paper 10 is irradiated with ultraviolet rays having a light emission peak at around 365 nm by the magenta fixing lamp 22, and magenta. The thermosensitive coloring layer 43 is photofixed. At this time, the illuminance sensor 28 detects the illuminance of each of the fixing lamps 21 and 22, and controls the output of each of the fixing lamps 21 and 22 based on the detection result to adjust the irradiation amount of the ultraviolet rays to an optimum value. Finally, a cyan image is thermally recorded on the cyan thermosensitive coloring layer 42. The recording paper 10 after the thermal recording of the cyan image is cut for each recording area by the cutter 30, discharged from the paper discharge outlet 31, and sequentially stacked on a paper tray (not shown).
[0018]
【The invention's effect】
As described above, according to the optical fixing device of the present invention, a yellow lamp unit composed of two yellow fixing lamps and a reflecting plate, and a magenta composed of two magenta fixing lamps and a reflecting plate. Lamp unit, one illuminance sensor that is provided on the opposite side of the fixing lamp across the reflector and detects the amount of ultraviolet light emitted from each fixing lamp, and two lamps that are provided on the reflector Since it has the daylighting hole for making the irradiation amount of the ultraviolet rays irradiated to the illuminance sensor the same, the parts cost can be reduced and the installation space for other parts can be secured sufficiently. In addition, there is no risk of measurement errors due to the use of multiple illuminance sensors.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the configuration of a color thermal printer embodying the present invention.
FIG. 2 is a cross-sectional view showing a configuration of a color thermal recording paper.
FIG. 3 is an enlarged cross-sectional view of the optical fixing device.
FIG. 4 is a top plan view of the optical fixing device.
[Explanation of symbols]
2 color thermal printer 10 color thermal recording paper 17 thermal head 20 light fixing device 21 yellow fixing lamp 22 magenta fixing lamp 23 reflector 24 yellow lamp unit 25 magenta lamp unit 28 illuminance sensor 29 daylighting hole 41 support 42 cyan heat sensitive Coloring layer 43 Magenta thermosensitive coloring layer 44 Yellow thermosensitive coloring layer

Claims (1)

A yellow thermosensitive coloring layer, a magenta thermosensitive coloring layer, and a cyan thermosensitive coloring layer are arranged in parallel in the transport direction of the color thermosensitive recording paper, and the yellow thermosensitive coloring layer and the magenta thermosensitive layer after thermal recording are arranged in parallel. A yellow fixing lamp and a magenta fixing lamp that perform light fixing by irradiating ultraviolet rays having a specific wavelength range to the color developing layer, and disposed on the opposite side of the color thermal recording paper with the fixing lamp interposed therebetween, In a light fixing device comprising a reflecting plate that reflects ultraviolet rays toward color thermal recording paper,
A yellow lamp unit composed of two yellow fixing lamps and a reflector; a magenta lamp unit composed of two magenta fixing lamps and a reflector;
One illuminance sensor provided on the opposite side of the fixing lamp across the reflector and detecting the amount of ultraviolet light emitted from each fixing lamp;
An optical fixing device comprising: a lighting hole provided on the reflecting plate for making the irradiation amount of ultraviolet rays irradiated from the two lamps to the illuminance sensor the same.

Images