JPH0369942A - Method for controlling temperature of solvent for image formation - Google Patents

Abstract

PURPOSE:To allow the application of a solvent for image formation without preheating time by previously setting the control temp. in the empty state of a tank higher by the temp. difference thereof than a desired application temp. CONSTITUTION:A heater 82 is disposed on the outside surface of the base of the main tank 80 and a thermistor 84 is likewise disposed on the outside surface of the base of the main tank 80. A temp. controller is connected to the thermis tor 84 and controls the heater 82 to the set temp. The control temp. in the empty state of the tank is previously kept higher than the desired application temp. of the solvent for image formation and this increased temp. difference is so maintained as to be the same as the temp. difference between the temp. at the point of the time when the accumulation of the solvent for image forma tion lower in temp. than the desired application temp. into the tank ends and the first tank temp. The temp. of the solvent for image formation is, therefore, exactly set at the desired application temp. at the time when the accumulation of the solvent for image formation ends actually. The application of the solvent for image formation is started without the preheating time in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to temperature control of an imaging solvent that is stored in a tank with a heater and applied to an imaging material by a rotating roller in the tank. Regarding the method.

[Conventional technology]

As an image-forming material that requires the application of an image-forming solvent as described above, for example, a heat-developable photosensitive material is known. (Published by Corona Publishing in 1982)
Pages 242-255 of , published in April 1978, Video Information 4
0 pages, Neblett's Handbook of Photography and Librograph 4- (Neblett's
Handbook of Photography an
dReprography) 7th Edition (7thEd
) Fan Nostrand Reinhold Company
-(Van No5trand Re1nhold C
Company), pages 32-33.

As for the method of obtaining a color image by heat development, a movable dye is released in an image form by heating.
A method of transferring this mobile dye to a dye fixing material (image receiving material) having a mordant using a solvent such as water, a method of transferring it to a dye fixing material using a high boiling point organic solvent, a method of transferring this mobile dye to a dye fixing material using a solvent such as water, and a method of transferring the mobile dye to a dye fixing material using a hydrophilic heat solvent built into the dye fixing material. There have been proposed methods in which the dye is transferred to a dye-fixing material, and a method in which the mobile dye is thermally diffusible or sublimable and is transferred to a dye-receiving material such as a support.

Specifically, as an apparatus for carrying out this type of image forming method, as disclosed in Japanese Patent Application Laid-open No. 59-75247, a color image is formed on a heat-developable photosensitive material using an exposure head in an exposure section. After exposing the photothermographic material to light, an image forming solvent such as water is applied to the photothermographic material using a roller, and this is sent to the thermal development section, where the image receiving material is brought into close contact with the photothermographic material after heat development and transferred to the transfer section. An image forming apparatus has been proposed which thermally transfers an image to an image receiving material in a transfer section.

Furthermore, an apparatus has been proposed in which two image forming materials, a photothermographic material and an image receiving material, are superimposed to perform development and transfer at the same time.

An image forming solvent coating device used in the above image forming apparatus is disclosed in, for example, Japanese Patent Laid-Open No. 63-94242.

[Problem to be solved by the invention]

In the above-mentioned image forming solvent coating apparatus, efficiency is improved by using a coating tank with a capacity as small as possible in order to stabilize the temperature. Furthermore, the image forming solvent in the coating section is replaced every time one sheet is coated. This is because the image-forming material is in contact with the roller, and gelatin, etc. on the image-forming surface peels off and adheres to the roller, rapidly staining the image-forming solvent in the coating tank. This is because it leaves dirt behind.

However, in such a configuration, the temperature in the image forming solvent storage section for replenishment is lower than that in the coating tank whose temperature is controlled for coating, so it must be replaced each time during the coating process as described above. The temperature inside the coating tank will drop below the desired temperature, and if the coating process continues, the coating amount will decrease and become unstable. Therefore, the preheating time required to raise this temperature to the desired set value is necessary. Required for each coating process. Therefore, there is a problem in that there is a limit to the reduction of the image forming processing interval time due to the time required between the coating processes.

An object of the present invention is to solve the above-mentioned problems, and to provide a method for controlling the temperature of an image forming solvent, which eliminates the need for preheating time without reducing the coating amount, and which has short coating treatment intervals and does not stain images. There is a particular thing.

[Means and effects for solving the problem] The above object of the present invention is to reduce the temperature of an image forming solvent stored in a tank having a heater and applied to an image forming material by a rotating roller in the tank. A control method for supplying an image forming solvent from an empty state of the tank, and when the amount reaches a desired amount, the temperature of the image forming solvent reaches from an initial temperature to a desired coating temperature. The required heating temperature when the tank is empty is set in advance, the tank is heated and controlled at that temperature, and after the desired amount of the image forming solvent is reached, the image forming solvent is applied at the desired temperature. This is achieved by controlling the temperature of the tank.

In other words, when the image forming solvent starts to accumulate in the tank, the temperature inside the tank starts to drop, and when it is completely accumulated, there will be a certain temperature difference, so the control temperature in the empty state of the tank should be adjusted in advance by this temperature difference. By keeping the temperature higher than the desired coating temperature, the temperature of the image forming solvent becomes exactly the desired coating temperature when the storage of the image forming solvent is actually completed. By changing the controlled temperature of the tank to the desired coating temperature at this point, the image forming solvent can be coated at a constant desired temperature without any preheating time.

The method of the present invention can be applied to an image forming apparatus using an image forming material that is a photothermographic material and an image receiving material as described above, and an image forming solvent may be used in either one or both materials. It can be configured to apply.

The photosensitive materials and image-receiving materials that are the image-forming materials used in the present invention are those in which visible images are obtained by developing and fixing latent images obtained by imagewise exposure in the presence of an image-forming solvent. It can be anything.

For example, photosensitive materials include heat-developable photosensitive materials,
U.S. Patent Nos. 4,430,415 and 4,483,9
No. 14, No. 4.500,626, No. 4.503.
1'37, JP-A-59-154445, JP-A No. 59-1
No. 65054, No. 59-180548, No. 59-21
No. 8443, No. 60-120356, No. 61-882
No. 56, No. 61-238056, etc.

The above-mentioned heat-developable photosensitive material basically consists of photosensitive silver halide, a binder, a dye-providing compound, a reducing agent (
In some cases, the dye-donating substance also serves as a reducing agent. Furthermore, organic silver salts and other additives can be contained as necessary.

The heat-developable photosensitive material may be one that gives a negative image or one that gives a positive image when exposed to light. Direct positive emulsion as a silver halide emulsion (there are two types: a method that uses a nucleating agent and a method that uses light fogging) to provide a positive image.
Either a method using a dye-donating compound or a method using a dye-donating compound that emits a positively diffusible dye image can be adopted.

There are various methods for transferring diffusible dyes, such as transferring to a dye fixing layer using an image forming solvent such as water, transferring to a dye fixing layer using a high boiling point organic solvent, and transferring to a dye fixing layer using a hydrophilic thermal solvent. A method of transferring the dye to a dye fixing layer having a dye-receiving polymer using the thermal diffusivity or sublimation of a diffusible dye has been proposed.
It can be any of them.

In addition, as the image forming solvent used for the above diffusion transfer,
For example, there is water, and this water includes not only so-called pure water but also water in the widely customary sense. Alternatively, a mixed solvent of pure water and a low boiling point solvent such as methanol, DMF, acetone, or diisobutyl ketone may be used. Furthermore, a solution containing an image formation accelerator, an antifoggant, a development stopper, a hydrophilic heat solvent, etc. may also be used.

[Embodiment]

Hereinafter, one embodiment of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a schematic diagram of an image forming apparatus to which the method of the present invention is applied.

A magazine 14 is disposed on the machine base 12 of the image forming apparatus 10, and a roll-shaped photothermographic material 16 is housed within the magazine 14.

The heat-developable photosensitive material 16 is pulled out from its outer periphery, cut into a predetermined length by a cutter 18, and then wound around the outer periphery of a rotating drum 20 in the six directions of arrows. The exposure head 22 corresponds to the outer circumference of this rotating drum 20.
is arranged, rotates the rotating drum 20 at high speed,
An image is exposed onto the wound photothermographic material 16.

After exposure, the photothermographic material 16 is transferred by rotating the rotating drum 20 in reverse (
direction of arrow B), the scraper 24 rotates the rotating drum 20.
The sheet is peeled off from the substrate and further conveyed by a pair of conveying rollers 25 and 27. Conveyance roller pair 25.27
is mechanically connected to a step motor (not shown) as a driving means, and is rotated by the step motor.

A water application section 26 is provided between the pair of conveyance rollers 25 and the pair of conveyance rollers 27 on the conveyance path of the photothermographic material 16 . A coating roller 64 rotated by an AC motor (not shown) is disposed in the water coating section 26, and the photothermographic material 16 is transferred to the coating roller 64 while being conveyed.
Water as an image forming solvent is applied by contacting the substrate.

The heat-developable photosensitive material 16 coated with water is transferred to the heat-developable transfer section 28.
It is now being sent to.

In the thermal development transfer section 28, a heating drum 34 and an endless pressure belt 36 serving as pressure contact means are arranged. Further, a halogen lamp 38 is disposed inside the heating drum 34, and the outer peripheral surface of the heating drum 34 is heated to about 90° C. by the halogen lamp 38.

The endless crimping belt 36 is wrapped around rollers 37, 39, 41.
．． 43, and its endless outer side is pressed against the outer peripheral surface of the heating drum 34. The winding roller 37 is mechanically connected to a step motor (not shown), and is rotated by the drive of this step motor. The photosensitive material 16 is pinched and conveyed and thermally developed.

Near the part where the endless pressure belt 36 is wound around the roller 37, a rubber overlapping roller 48 is placed so as to be pressed against and in contact with the outer peripheral surface of the heating drum 34. This overlapping roller 48 is also mechanically connected to a step motor (not shown), and is rotated by the drive of this step motor.

The image-receiving material 32 sent to the thermal development transfer section 28 is transferred by a superimposing roller 48 placed in pressure contact with the outer peripheral surface of the heating drum 34 (between the superimposing roller 48 and the outer peripheral surface of the heating drum 34). The heat-developable photosensitive material 16 is superimposed on the heating drum 34 and the endless pressure belt 36.
It is designed to be supplied between.

The heat-developable photosensitive material 16 is heated while being conveyed in a superimposed state with the image-receiving material 32 in the heat-developable transfer section 28, and the image is transferred to the image-receiving material 32 along with heat development, and an image is obtained on the image-receiving material 32. It looks like this.

A peeling plate 49 is arranged on the side of the thermal development transfer section 28 . The peeling plate 49 has a distal end close to the outer circumferential surface of the heating drum 34, moves together with the heating drum 34, engages with the photothermographic material 16 located inside, and receives the image of the photothermographic material 16. The material 32 is peeled off from the outer periphery of the heating drum 34.

A pair of separation rollers 50 are disposed below the peeling plate 49 and correspond only to both ends of the image receiving material 32 in the width direction.
Furthermore, a conveyor belt 52 is wound around the separation roller 50. This conveyor belt 52 engages only at both ends of the image receiving material 32 in the width direction, and transfers the image receiving material 32 to the photothermographic material 1.
6 and is bent and transported.

This separation roller 50 is mechanically connected to a step motor (not shown), and is rotated by the drive of this step motor.

The separated image-receiving material 32 is dried by a heater 54 and then sent onto a take-out tray 56 formed at the top of the machine stand 12.

On the other hand, the separated photothermographic material 16 is conveyed by a pair of conveying rollers 58 and sent to a waste photosensitive material storage box 59. This conveyance roller pair 58 is also mechanically connected to a step motor (not shown).
It is rotated by a step motor.

FIG. 2 is a sectional view of the water application section.

The photothermographic material 16 conveyed from the exposure section is held between a pair of conveyance rollers 25 as shown by the arrow, and then conveyed to the water application section 26 . The water application section 26 has a main tank 80 and a main tank 8.
It has an application roller 64 for applying the water contained in the photothermographic material 16 to the heat-developable photosensitive material 16. Water supply and drainage port 92a
is supplied from the water storage tank 90 to the main tank 80, and the discharge port 9
The water level is kept constant by overflowing from 2b to the water storage tank 90. In the middle of the path between the water supply and drainage port 92a and the water storage tank 90, the water storage tank 90 is connected from the discharge port 92b to the water storage tank 90.
There is a path connected to the drain by a solenoid valve 94, which opens when draining water.

A heater 82 is arranged on the bottom outer surface of the main tank 80,
A thermistor 84 is also located on the bottom exterior surface of the main tank 80. The temperature regulator (not shown) is the thermistor 8.
4, and controls the heater 82 to a set temperature.

Note that the thermistor 84 is located at the main tank 8 as described above.
In addition to the bottom outer surface of the 0, the temperature may also be measured in water or in the heater itself.

Next, the control method of this embodiment will be explained.

FIG. 3 shows the temperature control state of the main tank.

When the image forming apparatus is powered on and image formation has not started, the temperature of the main tank 80 is adjusted by the temperature controller to correspond to the water temperature in the water tank 90, which is lower than the desired coating temperature. It is controlled at a preset temperature tl higher than the desired coating temperature t2.

At the same time as the image formation starts, water flows into the main tank 80 from the water supply/drainage port 92a, and the temperature of the main tank 80 gradually decreases as shown by the slope A in the figure. When the water overflows at the discharge port 92b, the water supply is stopped, and at this point the temperature decrease stops, and the detected temperature reaches the desired application temperature t.
It will reach around 2. When the water supply to the main tank 80 is stopped, the temperature set by the temperature controller is changed to the temperature t2, and the temperature of the main tank 80 is changed to the temperature t2 so that the water inside the main tank 80 is stabilized at the desired coating temperature. controlled by

Therefore, water application is possible when the water supply to the main tank 80 is stopped, and since the time required for this water supply is short, the photothermographic material 16 after image exposure is transported without stopping or slowing down. Coating can be performed. Then, when the water application is completed, the solenoid valve 94 opens and the water in the main tank 80 is drained.

At this point, the controlled temperature of the main tank 80 is returned to the temperature tl.

When a plurality of images are formed, water in the main tank 80 is prevented from becoming contaminated by performing the water supply/drainage and temperature control for each -image. At this time, the above water supply and drainage time is short,
Since the state is ready for water application only within this time, the image forming time interval is not affected.

Although the temperature tl in the above embodiment is a preset temperature, changes in the water temperature of the water tank 90 can be handled by measuring the temperature of the water tank 90 and making corresponding settings on the temperature controller. This allows for more accurate temperature control.

Further, in this embodiment, the photothermographic material is coated with water, but it is also possible to apply the water to the image-receiving material, and it is also possible to apply the water to both materials.

〔Effect of the invention〕

According to the present invention, the control temperature in an empty state of the tank is set higher than the desired coating temperature of the image forming solvent in advance, and this increased temperature difference is used to accumulate the image forming solvent whose temperature is lower than the desired coating temperature in the tank. By making the temperature difference between the temperature at the time when the image forming solvent is finished and the initial tank temperature the same, the temperature of the image forming solvent can be set to exactly the desired coating temperature when the image forming solvent is actually accumulated. By changing the control temperature of the tank to the desired coating temperature at this point, coating can be performed at the same time as the storage of the image forming solvent is completed, and the image forming solvent can be coated at a constant desired temperature without any preheating time. can be started and the time between coating processes can be shortened.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of the image forming apparatus, FIG. 2 is a schematic sectional view of the water application section, and FIG. 3 is a diagram showing the temperature control state of the main tank. Codes in the figure: 10 Image forming device 16 Heat-developable photosensitive material 25.2
7-Transport roller pair 26 Water application section 28 Heat development transfer section 32-Image receiving material 34 Heating drum 36/Endless pressure belt
48-Overlapping roller 64-Water application roller 80
Main tank 82- Heater 84 Thermistor 9
0・Water tank 92b-Discharge port 92a Water supply/drainage port 94・Solenoid valve No. 1 Fig. 0 Fig. Fig. Question n

Claims (1)

[Claims] A method for controlling the temperature of an imaging solvent stored in a tank having a heater and applied to an imaging material by a rotating roller in the tank, the method comprising supplying the imaging solvent from an empty state of the tank. and setting in advance the heating temperature when the tank is empty, which is necessary for the temperature of the image forming solvent to reach the desired coating temperature from the initial temperature when the amount reaches the desired amount; A method for controlling the temperature of an image forming solvent, the method comprising heating the tank at that temperature and controlling the temperature of the tank at a desired temperature for applying the image forming solvent after a desired amount of the image forming solvent is reached.