JP4041980B2 - Thermal development method and thermal development apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat development method and a heat development apparatus capable of forming an image on a plurality of sizes of heat development photosensitive films.
[0002]
[Prior art]
In a conventional medical imager (heat development apparatus), photothermographic films (hereinafter simply referred to as “films”) of sizes of half cut (17 × 14), large angle (14 × 14), and large four cut (11 × 14) are used. In some cases, the same imager can be processed by transporting the film so that the main scanning direction is 14 inches, and other sizes, for example, six cuts, are processed by the dedicated imager. In such a case, whichever method is adopted, there is not much difference from the viewpoint of functional performance and cost.
[0003]
However, in recent years, in addition to the above three sizes, the short and long sides such as six cuts (8 × 10) used at the output of the ultrasonic imaging apparatus are both half cut (17 × 14), large angle (14 × 14), large There is a demand for an imager capable of processing a film having a size that does not coincide with four cuts (11 × 14).
[0004]
In addition, the imager employing the heat development process has the following problems specific to heat development. That is, in the heat development process, as a heating and conveying means for heating the film, as shown in the following Patent Document 1, when a method of conveying while holding the film by a heating drum and a plurality of opposing rollers is adopted, An elastic layer such as silicon rubber may be provided on the surface of the heating member in order to make the contact between the heating drum and the opposing roller uniform and to make the surface temperature of the heating drum uniform.
[0005]
However, as the elastic layer is processed by the photothermographic film, the organic acid or higher fatty acid contained in the photothermographic film is volatilized from the film by heating and drifts around the elastic layer. Attacks and tries to inhibit the cross-linking of silicon rubber. Further, when the volatilized organic acid or the like aggregates and adheres to the surface of the heating drum, and the film passing trace or the like is formed by the aggregate, the image may be affected.
[0006]
In addition to this, coupled with repeated heating and cooling of the heating drum itself, the elastic layer of the film passage part swells and eventually begins to crack on the surface, which is eventually transferred to the film. The Rukoto. This is because the contact state between the heating drum and the film is not uniform, and heat transfer is not uniform over the entire surface of the heating drum. If the film passing position in the heat developing section is only 14 inches, the effect is relatively large even if three sizes of half cut (17 × 14), large angle (14 × 14), and large four cut (11 × 14) are processed. It can be used until the elastic layer is cracked.
[0007]
However, if the size different from 14 inches is processed by the same imager (heat developing apparatus), the swelling marks and the passage marks corresponding to the film edges are generated in the portions different from the 14 inch width ends. When processing a film of a size, there was a problem that it appeared in the image.
[0008]
Patent Document 2 listed below introduces a new film when an exposed film is carried into a heat developing section and developed by heating with a heating drum, and when a film having a different size is carried into the heat developing section. By waiting a predetermined size of film for a predetermined time, it is delayed from being carried into the heat developing section. An image recording apparatus is disclosed in which the surface temperature is made uniform by continuing the rotation of the heating drum and the heating by the heat source during the standby state, but the image defect caused by the heat treatment of the photothermographic film is disclosed. Does not deal with.
[0009]
The following Patent Document 2 discloses a method for removing dust having a sticky surface when a photothermographic film having a latent image formed thereon is sandwiched between a heating drum and an endless belt and conveyed by a heating unit to obtain a visible image. Disclosed is a heat developing device in which dust adhered to the heating drum is removed by disposing the means in contact with the heating drum to prevent the occurrence of dot-like image defects. It does not deal with image defects caused by the heat treatment.
[0010]
[Patent Document 1]
Japanese National Patent Publication No. 10-500497
[0011]
[Patent Document 2]
JP-A-11-65070
[0012]
[Patent Document 3]
Japanese Patent Laid-Open No. 11-65073
[0013]
[Problems to be solved by the invention]
In view of the above-described problems of the prior art, the present invention provides a thermal development method and a thermal development apparatus that are less affected by an image when the thermal development photosensitive film is changed from a small size to a large size when performing a thermal development process. The purpose is to provide.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the thermal development method according to the present invention comprises: Pre-loaded based on film size information pre-attached to input image information Sheet-shaped photothermographic film of multiple sizes Out of Selecting and transporting the size; exposing the transported photothermographic film to form a latent image; and heating and visualizing the photothermographic film having the latent image formed thereon by a heating unit; A heat development method comprising: Selected based on film size information Photothermographic film Size of Is changed from a small size to a large size, the film contact surface of the heating unit is cleaned.
[0015]
According to this thermal development method, after the thermal development process is continuously performed on the small-sized photothermographic film, before the thermal development process is performed after changing to a large-size thermal development photosensitive film, the heating unit Since the film contact surface is cleaned, the influence on the image due to the passage trace of the small-sized photothermographic film can be reduced.
[0016]
The heat development apparatus according to the present invention comprises: A heat development apparatus for forming an image on a sheet-like heat-developable photosensitive film based on input image information, each comprising: Size Different Sheet-shaped photothermographic film each Can be loaded plural Film placing means; conveying means for conveying the photothermographic film on the film placing means; exposure means for forming a latent image on the conveyed photothermographic film; and heat on which the latent image is formed A heat developing means having a heating part for visualizing the development photosensitive film, and a cleaning means for cleaning the film contact surface of the heating part; , Based on the film size information attached to the input image information in advance, the sheet-like photothermographic film loaded in any of the plurality of film mounting means is selected and conveyed to the conveying means, Selected based on the film size information The photothermographic film was changed from small to large. Judged When the cleaning means controls to clean the film contact surface of the heating unit And a control unit It is characterized by that.
[0017]
According to this thermal development apparatus, the above thermal development method can be executed, and after the thermal development process is continuously performed on a small-sized photothermographic film, the thermal development process is changed to a large-sized photothermographic film. Since the film contact surface of the heating portion is cleaned before execution, the influence on the image due to the passage trace of the small-sized photothermographic film can be reduced.
[0018]
In the above heat development apparatus, it is preferable that the cleaning unit is configured to be pressure-bonded to the film contact surface when cleaning and to be separated when not cleaning. Since the cleaning unit is separated from the film contact surface during non-cleaning, the load on the heating unit can be reduced when the heating unit is moved by rotation or the like.
[0019]
Also, When the control unit counts the number of small-size film processed continuously based on the film size information and determines that the selected photothermographic film has been changed from a small size to a large size In addition, it is preferable to perform control so that the film contact surface of the heating unit is cleaned when the number of small-size film treatments reaches a predetermined number. In addition The heating unit has an elastic layer provided on the surface and a smooth surface layer preferably formed of a fluororesin or the like provided on the outer surface of the elastic layer, so that the smooth surface layer that is a film contact surface This surface is preferable because it has a good releasability, so that the cleaning effect by the cleaning means is increased.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a main part of the thermal development apparatus according to this embodiment. FIG. 2 is a perspective view of the heat development apparatus of FIG. 1, showing a state in which the first loading unit is pulled out. FIG. 3 is a view schematically showing an exposure unit of the heat development apparatus of FIG.
[0021]
As shown in FIG. 1, a heat developing apparatus 100 includes first and second loading units 11 and 12 for loading a package in which a predetermined number of heat developable photosensitive films, which are sheet-like heat developable photosensitive materials, are packaged, and a film. A supply unit 110 having a conveyance unit 5 that conveys the images one by one for exposure and development, an exposure unit 120 that exposes a film fed from the supply unit 110 to form a latent image, and a latent image is formed. A heat developing unit 130 that thermally develops the developed film, and a cooling and conveying unit 150 including a densitometer 200 that obtains density information by measuring the density of the developed film, a conveying roller 144, and the like.
[0022]
The first and second loading units 11 and 12 of the supply unit 110 can be loaded with films of different sizes, and the films are conveyed one by one from the first loading unit 11 or the second loading unit 12. It is conveyed in the arrow direction (1) of FIG. 1 by the part 5 and the conveyance roller pair 139, 141. Then, the film is conveyed in the arrow direction (2) and a latent image is formed by the exposure unit 120. Next, the film is conveyed in the arrow direction (3) by the pair of conveyance rollers 142 and 143, and the latent image is visible in the heat developing unit 130. Then, it is further conveyed in the direction of arrow (4), cooled by the cooling conveyance unit 150, and then discharged to the discharge unit 160. The conveyance roller pairs 139, 141, 142, 143 and the like are rotationally driven by a motor 151 and the like in FIG. 4, and the motor 151 and the like are controlled by a control unit 152 constituted by a central processing unit (CPU) as shown in FIG.
[0023]
As shown in FIG. 2, the first loading unit 11 of the heat development apparatus 100 includes a storage tray unit 3 that can store a film by loading the film in a film package state, and a film that is provided integrally with the storage tray unit 3. A roller-feed type transport unit 5 for transporting the sheets one by one to the outside of the delivery device, and a removal unit 6 that winds and removes the barrier bag of the film package that is integrally provided on the back side of the storage tray unit 3 and loaded. And comprising.
[0024]
The first loading unit 11 is configured to be accommodated in the apparatus housing 1a of the heat developing apparatus 100 and to be pulled out from the apparatus housing 1a. That is, the entire storage tray portion 3 is configured to be able to be pushed into and pulled out from the front of the apparatus housing 1a with respect to the apparatus housing 1a, and when loaded from the apparatus housing 1a in the direction H 'as shown in FIG. Thus, the film package can be loaded and maintained, and when it is pushed into the apparatus housing 1a in the direction H in FIG. 2, the light from the outside is blocked and the film can be transported at the transport position. As described above, the storage tray unit 3 of the first loading unit 11 is configured to be movable between the transport position inside the apparatus and the loading position outside the apparatus.
[0025]
Next, the conveyance unit and the removal unit in FIG. 2 will be described with reference to FIGS. FIG. 9 is a side view schematically showing a transport unit provided in the first loading unit 11 of FIG. FIG. 10 is a side sectional view schematically showing a barrier bag removing unit in the first loading unit 11 of FIG. FIG. 11 is a partially broken perspective view of a film package that can be loaded into the first and second loading sections of FIGS. 1 and 2.
[0026]
As shown in FIG. 9, the transport unit 5 is configured so that the transport roller 91 that contacts the surface BC of the film F placed in a stacked state on the mounting table 4 with a predetermined pressing force P11 rotates in the rotation direction r. The upper film F is fed to the nip roller pair 92, 93 side, and the driving roller 92 is transported while applying the nip force P12 from the driven roller 93 side to the driving roller 92 side with the film F being sandwiched between the two rollers 92, 93. The sheet is conveyed in the conveyance direction J by rotating in the rotation direction r ′ in synchronization with 91.
[0027]
In addition, when the film is transported as described above, the uppermost film F and the one or two films below it may be sent out by the transport roller 91 and transported by the nip roller pair 92, 93. It is composed of a reversible roller with a torque limiter. When a plurality of films F are sandwiched between the pair of nip rollers 92 and 93, the friction coefficient between the films F is lower than the friction coefficient between the driving roller 92 and the film F, so that the torque from the driving roller 92 is on the driven roller 93 side. The torque limiter is detected without being transmitted to the drive roller 92, and the driving roller 92 and the transport roller 91 synchronized therewith are reversely rotated to return the excessively transported film F to its original state.
[0028]
As shown in FIG. 11, the film package P that can be loaded in the storage tray unit 3 is, for example, stacked and positioned on a positioning member D that is positioning means as a bundle of about 125 pieces of a film F having a half-cut size. In the state, it is light-tightly accommodated in the barrier bag B which is a light shielding means. At the side end of the barrier bag B, a plurality of engaging holes a that engage with the engaging claws 26 (FIG. 3) in the barrier bag removing device are formed.
[0029]
A barrier bag removing section 6 is provided on the depth side of the storage tray section 3 in FIG. As shown in FIG. 10, the barrier bag removing unit 6 loads the film package P of FIG. 11 onto the mounting table 4 of the storage tray unit 3 of FIG. 2, and one of the guide roller pairs 11 </ b> A is a two-dot chain line of FIG. 10. The plurality of engaging holes a at the side ends of the film package P are engaged with the engaging claws 26 in the state of being moved upward, and then the side end surfaces of the film package P are sandwiched by the guide roller pair 11A. A driving roller 30 provided around 26 is driven to rotate in the rotation direction c, and the barrier bag B is removed by winding the barrier bag B around the driving roller 30, and the laminated film positioned on the positioning member D F is exposed in the storage tray section 3. Before removing the barrier bag B, the other side end face b of the barrier bag B is cut so as to be easily wound.
[0030]
Next, an alignment mechanism for positioning and aligning the film so as to be conveyed on the basis of the front side of the apparatus main body in the first and second loading sections of FIG. 1 will be described with reference to FIG. 12A is a diagram showing the storage tray portion of FIG. 2 including a film positioning mechanism, and is a cross-sectional view (a) showing a state before the storage tray portion is broken in the width direction of the film and before alignment. It is sectional drawing (b) which shows the state after alignment.
[0031]
As shown in FIGS. 12A and 12B, the storage tray unit 3 includes a mounting table 4 on which the film F is mounted, and a storage tray provided around the mounting table 4 so as to include the mounting table 4 therein. 5 is provided. The mounting table 4 is composed of a flat plate-like member, and has a stepped recess 7 serving as a storage space for the push-up plate 11 at the center.
[0032]
The storage tray 3 further includes a push-up plate 11B provided so as to be accommodated in the stepped recess 7 of the mounting table 4, and push-up members 14A provided on the left and right in the drawing for raising the push-up plate 11B. 15A and motors M1 and M2 as driving means for separately driving the push-up members 14A and 15B, and an alignment mechanism for aligning the film F laminated on the mounting table 4 at a fixed position is configured. Yes.
[0033]
The push-up plate 11B is a rectangular plate-like member that directly supports the film F from below, and is accommodated so as to support the film in the step recess 7 when not operating, and is lifted from the step recess 7 by the lift members 14A and 15A during operation. The film F is moved upward to lift the film F on the mounting table 4 to the transport position of the transport unit 5 in FIG.
[0034]
The film F is removed from the film package P of FIG. 11 loaded in the storage tray unit 3 by the barrier bag removal unit 6 of FIG. It is exposed at. In this state, the push-up members 14A and 15A are provided on the left and right in the width direction of the film F perpendicular to the transport direction of the film F, operate individually by the motors M1 and M2, and lift the push-up plate 11 upward. At this time, as shown in FIG. 12 (b), the push-up member 14A is moved upward by the motor M1 without operating the push-up member 15A, and the push-up plate 11B is tilted and lifted upward. Can be tilted, and the side edges F1 of the film F are aligned.
[0035]
Thereafter, when the other motor M2 is driven to move the push-up member 15A upward, the push-up plate 11B returns to the horizontal state, the film F on the mounting table 4 returns to the horizontal position, and the uppermost plate As shown in FIG. 9, the film F comes into contact with the transport roller 91 of the transport unit 5 at the transport position and can be transported. Then, the transport roller 91 and the nip roller pairs 92 and 93 are driven, and the uppermost film F can be separated from the underlying film and transported in the transport direction J.
[0036]
As described above, the film F can be aligned on the front side of the apparatus (the front side in FIG. 2 and the left side in FIG. 9) in the storage tray portion 3 in FIG. Accordingly, the film F is conveyed as (1) and (2) in FIG. 1 with the side edges aligned with respect to the front side of the apparatus regardless of the size, and is conveyed to the heating drum 14. A film alignment mechanism that aligns the side edges of the film with the front side of the apparatus may also be provided on the upstream side of the conveying roller pair 142 of the exposure unit 120 in FIG. Each configuration of the second loading unit 12 is the same as that of the first loading unit 11 described above.
[0037]
As described above, since the film F is conveyed in the heat developing apparatus 100 in a state where the side edges thereof are aligned with respect to the front side of the apparatus (one-side reference conveying method), access to the film, particularly a small size film, is possible. This is preferable because it is easy to handle jam trouble.
[0038]
Next, the exposure unit will be described. As shown in FIG. 3, the exposure unit 120 deflects the laser light L, which has been intensity-modulated based on the image signal S, by the rotary polygon mirror 113 to perform main scanning on the film F, and converts the film F into the laser light L. On the other hand, it is sub-scanned by relative movement in a direction substantially perpendicular to the main scanning direction, and a latent image is formed on the film F using the laser beam L.
[0039]
A more specific configuration of the exposure unit 120 will be described below. In FIG. 3, an image signal S that is a digital signal output from an external image signal output device 121 is converted into an analog signal by a D / A converter 122 and input to a modulation circuit 123. Based on the analog signal, the modulation circuit 123 controls the driver 124 of the laser light source unit 110a to irradiate the laser beam L modulated from the laser light source unit 110a.
[0040]
The laser light L emitted from the laser light source unit 110a passes through the lens 112, is converged only in the vertical direction by the cylindrical lens 115, and rotates on the polygonal mirror 113 rotating in the direction of arrow A in FIG. Incident light is incident as a vertical line image. The rotary polygon mirror 113 reflects and deflects the laser beam L in the main scanning direction, and the deflected laser beam L passes through an fθ lens 114 including a cylindrical lens formed by combining two lenses and then enters the optical path. Reflected by a mirror 116 that extends in the main scanning direction, and on the scanned surface 117 of the film F that is conveyed (sub-scanned) in the arrow Y direction by the conveying device 142, the direction of the arrow X Repeat the main scan. That is, the laser beam L is scanned over the entire surface to be scanned 117 on the film F.
[0041]
The cylindrical lens of the fθ lens 114 converges the incident laser light L on the scanning surface 117 of the film F only in the sub-scanning direction, and the distance from the fθ lens 114 to the scanning surface. Is equal to the focal length of the entire fθ lens 114. As described above, the exposure unit 120 includes the fθ lens 114 including the cylindrical lens and the mirror 116 so that the laser light L is once converged on the rotary polygon mirror 113 only in the sub-scanning direction. Therefore, even if the rotary polygon mirror 113 is tilted or the shaft is shaken, the scanning position of the laser beam L is not shifted in the sub-scanning direction on the surface to be scanned 117 of the film F. It can be formed. The rotary polygon mirror 113 has an advantage that it is superior in scanning stability compared to other optical polarizers such as a galvanometer mirror. As described above, a latent image based on the image signal S is formed on the film F.
[0042]
The details of a specific chemical reaction in which a latent image is formed as described above will be described with reference to FIG. FIG. 7 is a cross-sectional view of a film F made of a heat developing material, and is a diagram schematically showing a chemical reaction in the film F at the time of exposure.
[0043]
In the film F, a photosensitive layer mainly composed of a heat resistant binder is formed on a support (base layer) made of PET, and a protective layer mainly composed of a heat resistant binder is further formed thereon. The photosensitive layer contains silver halide grains, silver behenate (Beh. Ag), which is a kind of organic acid silver, and a reducing agent and a toning agent. Moreover, the back surface layer which has a heat resistant binder as a main component is provided also in the back surface of the support body.
[0044]
When the exposure unit 120 irradiates the film F with the laser beam L during exposure, the silver halide grains are exposed to a region irradiated with the laser beam L as shown in FIG. Is done.
[0045]
4 to 6 are diagrams showing a configuration of the heat developing unit 130 for heating the film F. More specifically, FIG. 4 is a perspective view of the heat developing unit 130, and FIG. 6 is a cross-sectional view taken along the line IV-IV and viewed in the direction of the arrow, and FIG. 6 is a view of the configuration of FIG. 4 viewed from the front.
[0046]
The thermal development unit 130 includes a heating drum 14 as a heating member that can be heated while holding the film F in close contact with the outer periphery. The heating drum 14 has a function of forming the latent image formed on the film F as a visible image by maintaining the film F at a predetermined heat development time above a predetermined minimum heat development temperature. Here, the minimum heat development temperature is a minimum temperature at which the latent image formed on the film F starts to be thermally developed, and is 95 ° C. or more, for example. On the other hand, the heat development time refers to a time that should be maintained at a temperature equal to or higher than the minimum heat development temperature in order to develop the latent image on the film F to a desired development characteristic. In addition, it is preferable that the film F is a thing which is not thermally developed substantially at 40 degrees C or less.
[0047]
The content of a specific chemical reaction in which a latent image is visualized by the above heating will be described with reference to FIG. FIG. 8 is a cross-sectional view similar to FIG. 7 schematically showing a chemical reaction in the film F during heating.
[0048]
When the film F is heated to a temperature equal to or higher than the minimum heat development temperature, silver ions (Ag +) are released from the silver behenate as shown in FIG. 8, and the behenic acid released from the silver ions forms a complex with the toning agent. To do. Thereafter, silver ions are diffused, and a reducing agent acts on the exposed silver halide grains as nuclei, and a silver image is formed by a chemical reaction. Thus, the film F contains photosensitive silver halide grains, an organic silver salt, and a silver ion reducing agent, and is not substantially thermally developed at a temperature of 40 ° C. or lower, for example, at a temperature of 95 ° C. or higher. Heat developed.
[0049]
As shown in FIGS. 4 and 5, a plurality of rotatable opposing rollers 16 having a smaller diameter than the heating drum 14 as a guide member and a pressing member are provided outside the heating drum 14. Are arranged so as to face each other in parallel.
[0050]
The opposing roller 16 is made of stainless steel, and the upstream three pieces 16a, 16b, 16c are configured as solid large-diameter rollers having a diameter of, for example, 12 mm, and the opposing roller 16d adjacent to the downstream and the most downstream opposing roller The remaining counter rollers 16 up to 16e are formed into tubular small diameter rollers having a diameter of, for example, 8 mm. The counter roller 16 preferably has a heat capacity of 0.16 kJ / K or more, and the stainless steel as the material of the counter roller 16 has a heat capacity of about 0.18 kJ / K.
[0051]
At both ends of the heating drum 14, three guide brackets 21 supported by the frame 18 are provided on one side. By combining the guide bracket 21, opposing C-shapes are formed at both ends of the heating drum 14.
[0052]
The guide bracket 21 integrally holds a plurality of opposing rollers 16 at both ends, and the holding position by the guide bracket 21 can be adjusted. That is, by adjusting the position of the guide bracket 21, the positions of the plurality of opposing rollers 16 with respect to the heating drum 14 can be adjusted. Thereby, since the parallelism between the heating drum 14 and the opposing roller 16 in the axial direction of the heating drum 14 can be adjusted appropriately, the film can be uniformly adhered to the outer peripheral surface of the heating drum 14. In particular, when a smooth surface layer such as a fluororesin is provided on the outer peripheral surface of the heating drum 14 as described later, density unevenness is likely to occur due to such a deviation in parallelism, but the parallelism can be adjusted. By configuring, it is possible to realize a configuration capable of preventing such density unevenness.
[0053]
Each guide bracket 21 has nine elongated holes 42 extending in the radial direction. From this long hole 42, shafts 40 provided at both ends of the opposing roller 16 protrude. One end of each coil spring 28 is attached to the shaft 40, and the other end of each coil spring 28 is attached near the inner edge of the guide bracket 21. Accordingly, each counter roller 16 is urged toward the outer periphery of the heating drum 14 with a predetermined force based on the urging force of each coil spring 28. When the film F enters between the outer periphery of the heating drum 14 and the opposing roller 16, the film F is pressed against the outer peripheral surface of the heating drum 14 with such a predetermined force, thereby heating the film F uniformly over the entire surface. To do.
[0054]
A shaft 22 coaxially connected to the heating drum 14 extends outward from the end member 20 of the frame 18 and is rotatably supported by the end member 20 by a shaft bearing 24. A gear (not shown) is formed on a rotating shaft 23 of a microstep motor (not shown) disposed below the shaft 22 and attached to the end member 20. On the other hand, a gear is also formed on the shaft 22. The power of the microstep motor 155 (FIG. 15) is transmitted to the shaft 22 through a timing belt 25 (a belt on which gears are engraved) that connects both gears, whereby the heating drum 14 rotates. Note that power transmission from the rotary shaft 23 to the shaft 22 may be performed via a chain or a gear train instead of a timing belt.
[0055]
As shown in FIG. 6, in the present embodiment, the opposing roller 16 is provided in the circumferential direction of the heating drum 14, and the two reinforcing members 30 (FIG. 6) connect the both end members 20 of the frame 18. It connects and supports the both-ends member 20 additionally.
[0056]
A plate-like heater 32 is attached to the inner periphery of the heating drum 14 over the entire periphery, and the outer periphery of the heating drum 14 is heated under the control of the control electronic device 34 shown in FIG. Yes. Power is supplied to the heater 32 through a slip ring assembly 35 connected to the electronic device 34. The heater 32 is attached to the inner periphery of the heating drum 14 in order to heat the outer peripheral surface of the heating drum 14. For example, an etched resistive foil heater can be used.
[0057]
The electronic device 34 for controlling the heater rotates together with the heating drum 14 so that the electric power supplied to the heater 32 can be adjusted according to the temperature information sensed by the temperature detecting means disposed on the heating drum 14. It has become. The control electronic device 34 controls the outer surface temperature of the heating drum 14 by controlling the heater 32 so that the temperature is suitable for the development of the specific film F. In the present embodiment, the heating drum 14 can be heated to a temperature of 60 ° C to 160 ° C.
[0058]
Here, it is preferable to maintain the temperature in the width direction of the heating drum 14 within 2.0 ° C. (particularly within 1.0 ° C.) by the heater 32 and the control electronic device 34. In the present embodiment, the temperature is maintained within 0.5 ° C.
[0059]
As shown in FIG. 5, the heating drum 14 includes a rotatable cylindrical aluminum support tube 36, a flexible elastic layer 38 made of silicon rubber or the like attached to the outside of the support tube 36, and an elastic layer. And a smooth surface layer 39 formed as an outermost peripheral surface by coating the outer periphery of 38 with a fluororesin by coating or the like.
[0060]
The thickness and thermal conductivity of the elastic layer 38 are selected so that continuous processing of the plurality of films F can be performed efficiently, and the thermal conductivity is preferably 0.5 W / k or more. The hardness of the elastic layer 38 is preferably JIS-A hardness 20 to 70 degrees. The elastic layer 38 may be indirectly attached to the support tube 36.
[0061]
The elastic layer 38 can be composed of rubber or a rubber-like member, and the rubber or rubber-like member widely includes various materials having elasticity similar to that of the rubber material in addition to various rubber materials and thermoplastic elastomers. For example, various rubber materials, resin materials, thermoplastic elastomers and the like may be used alone or in combination. In this case, the various rubber materials are not limited. For example, in addition to a solid rubber material, a liquid reaction cured product obtained by curing a liquid viscoelastic body may be used.
[0062]
Solid rubber materials include, for example, ethylene propylene terpolymer (EPDM), butyl rubber, polyisobutylene, ethylene propylene rubber, chlorofrene rubber, natural rubber, styrene butadiene rubber, butadiene rubber, styrene-isobrene-styrene, For polymers using styrene-butadiene-styrene, urethane rubber, etc. alone or in combination, vulcanizing agents, cross-linking agents, vulcanization accelerators, vulcanization acceleration assistants conventionally used in the rubber industry in general. And vulcanized (or cross-linked) containing chemicals such as an agent, tackifier, filler, plasticizer, anti-aging agent, and solvent.
[0063]
The liquid rubber material includes, for example, urethane, liquid polybutadiene, modified silicon, silicon, polysulfide and the like. In addition, it is preferable to use these materials by adding a predetermined amount of a curing agent for solidification, mixing and reaction curing. The elastic layer 38 may be formed in a dense state or a sponge shape.
[0064]
Examples of the fluororesin applied to form the smooth surface layer 39 include polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), tetrafluoroethylene and herfluoroalkoxy. Compounds such as a copolymer of ethylene (PFA), a copolymer of ethylene and tetrafluoroethylene (ETFE), and a copolymer of tetrafluoroethylene and hexafluorobroylene (FEP) are used.
[0065]
When the film F is heated around the heating drum 14 for heat development, for example, a gas containing a chemical component such as an organic acid is generated, but fluorine that constitutes the smooth surface layer 39 provided on the surface of the elastic layer 38. Since the resin has chemical resistance, it does not react with gas components such as organic acids and does not deteriorate. In addition, the fluororesin blocks such gas components from permeating, and the elastic layer 38 made of silicon rubber or the like does not come into contact with gas components such as organic acids, so that the gas components do not deteriorate or deteriorate. . Therefore, the elastic layer 38 hardly changes in its shape and physical properties over time, so that the initial elastic force and thermal conductivity can be maintained.
[0066]
The thickness of the smooth surface layer 39 is preferably 10 μm or more from the viewpoint of preventing deterioration of the elastic layer 38 due to a gas component such as an organic acid, and preferably 60 μm or less from the viewpoint of preventing uneven density.
[0067]
Further, the urging force of the coil spring 28 determines the pressing force of the facing roller 16 so that the film F is securely adhered to the outer peripheral surface of the heating drum 14 and is stably conveyed while receiving sufficient heat transfer. Therefore, care must be taken in selecting the value. That is, if the biasing force of the coil spring 28 is too small, heat is conducted non-uniformly to the film F, so that image development may be incomplete, and film conveyance may become unstable.
[0068]
Next, the cleaning unit 13 provided in the heat development apparatus 100 of FIG. 1 will be described with reference to FIGS. FIG. 13 is an enlarged front view partially showing the cleaning unit and the heating drum in FIG. FIG. 14 is a perspective view showing a cleaning unit provided in the heat development apparatus of FIG.
[0069]
As shown in FIG. 1, the thermal development apparatus 100 includes a cleaning unit 13 for cleaning the surface of the heating drum 14 below the heating drum 14 in the thermal development unit 130. As shown in FIGS. 13 and 14, the cleaning unit 13 winds the cleaning web 13a having substantially the same width as the longitudinal dimension of the heating drum 14, the pressing roller 13b that presses the cleaning web 13a, and the cleaning web 13a. A take-out roller 13c that can be rotated so as to be drawn out from the taken state toward the pressing roller 13b, a take-up roller 13d that is rotated so as to wind up the cleaning web 13a from the pressing roller 13b side, and the rollers 13b to 13d. A chassis 13e to be accommodated.
[0070]
The cleaning unit 13 is moved in the arrow direction T from the solid line position in FIG. 13 by the moving unit 153 (FIG. 15), the cleaning web 13a comes into contact with the surface of the heating drum 14 (the surface to which the film contacts), and is pressed by the pressing roller 13b. It is pressed against the surface of the heating drum 14 to perform pressure bonding to perform cleaning, and after the cleaning is completed, it moves in the arrow direction T ′ so as to be separated from the surface of the heating drum 14. The moving unit 153 can be configured to move the chassis 13e in the directions T and T ′ by a known reciprocating mechanism using, for example, a motor, a wire, and a pulley, but is not limited thereto.
[0071]
As described above, the cleaning unit 13 is configured such that the cleaning web 13a is pressed against the surface of the heating drum 14 at the time of cleaning and is separated at the time of non-cleaning, so that the heating drum 14 is rotated when the heating drum 14 rotates for film heating. There is no increase in the load on.
[0072]
The cleaning web 13a is composed of a long sheet made of an absorbent material such as a nonwoven fabric, and is resistant to the heat resistance that can withstand the temperature of the heating drum 14 and the contact with the deposits of aggregates such as organic acid and MEK. It has chemical resistance, and is attached to the surface of the smooth surface layer 39 of the heating drum 14 by being pressed from the pressing roller 13b and pressure-adhered, thereby effectively adsorbing the adhered matter on the surface.
[0073]
When the winding roller 13d is rotationally driven in the rotational direction r of FIG. 14 by the cleaning motor 154 (FIG. 15) as the rotational driving means, the unused portion of the cleaning web 13a is wound around the feeding roller 13c. The pressure roller 13b is brought into contact with the surface of the smooth surface layer 39 of the heating drum 14 to perform cleaning, and the used cleaning web 13a is taken up by the take-up roller 13d.
[0074]
At the time of the cleaning, the heating drum 14 rotates in the rotation direction R so that the cleaning is performed on the entire outer peripheral surface of the heating drum 14. At this time, the cleaning web 13a moves in the direction w in FIG. That is, the cleaning web 13a moves from the feed roller 13c to the winding roller 13d in the direction w in FIG. 13 while being in contact with the surface of the smooth surface layer 39 of the rotating heating drum 14 by the pressing roller 13b. Done.
[0075]
Note that while the heating drum 14 rotates in the rotation direction R, the cleaning web 13a in a stopped state may contact the surface of the smooth surface layer 39 of the heating drum 14 to perform cleaning. In this case, after the cleaning is completed and the cleaning unit 13 moves in the arrow direction T ′ in FIG. 13 and moves away from the heating drum 14, the cleaning web 13 a is fed out so that the unused portion is positioned on the pressing roller 13 b. It is preferable to prepare for the next cleaning by winding a little around the take-up roller 13d.
[0076]
Next, the control system of the cleaning unit 13 will be described with reference to FIG. FIG. 15 is a block diagram showing a control system of the cleaning unit 13 shown in FIGS.
[0077]
The control unit 152 shown in FIG. 4 includes a microstep motor 155 for the heating drum 14 and a cleaning unit based on film size information included in the accompanying information attached to the image information received from the external image signal output device 121 shown in FIG. The 13 moving parts 153 and the cleaning motor 154 are controlled. That is, whenever the control unit 152 receives the image information including the image signal S, the control unit 152 checks the film size information of the incidental information, and when it detects that the film has been changed from the small size to the large size, it temporarily stops the film conveyance. Then, the heating drum 14 is rotated by the micro step motor 155, the moving unit 153 is operated and moves in the direction T in FIG. 13, and the cleaning web 13a is pressed against the surface of the rotating heating drum 14 by the pressing roller 13b. Clean the surface.
[0078]
Next, the film position on the heating drum in the case where films of different sizes are conveyed from the first and second loading sections 11 and 12 in the image forming apparatus 100 of FIGS. 1 and 2 will be described with reference to FIG. . FIG. 16 is a right side view of the heating drum of FIG. 1 (the counter roller and the like are omitted).
[0079]
When the film is conveyed to the heating drum 14 in FIG. 16, the film is conveyed so that the side end portion on the front side of the apparatus is along the reference line G <b> 0 in FIG. 16 on the outer peripheral surface of the heating drum 14. In this case, regardless of the size, the film is conveyed with the side edges aligned with the front side of the apparatus as shown in FIG. 9B, so that any size film can be heated along the reference line G0. It is heated while being conveyed on the outer peripheral surface of 14.
[0080]
For example, a relatively small size film (such as six cuts having a width C of 8 or 10 inches) has a side edge of the film along the reference line G0, and the other side edge is a small size line G1 determined by the width C of the film. Along the heating drum 14. In addition, a relatively large size film (half-cut, large angle, large partition, etc. having a width D of 14 inches) has a side edge along the reference line G0 and the other side edge determined by the film width D. Along the heating drum 14.
[0081]
As shown in FIG. 16, since the film is conveyed on one side reference along the reference line G0, a relatively small size film is conveyed while being continuously heated many times on the heating drum 14, and then relatively large. When a film of a size is heated and conveyed, a single passage mark formed from an aggregate such as an organic acid generated by film heating during the conveyance of a small size film may affect the image. For this reason, when the film is changed from the small size to the large size, the cleaning unit 13 of FIGS. 13 to 15 operates and the cleaning web 13 a cleans the surface of the heating drum 14 as described above. Thereby, since the passage trace which consists of aggregates, such as an organic acid, can be removed, even if it processes a large sized film after the process of a small sized film, a possibility of affecting an image can be reduced.
[0082]
In this case, as shown in FIGS. 5 and 6, since the smooth surface layer 39 made of a fluororesin formed on the surface of the elastic layer 38 of the heating drum 14 has good releasability, the surface of the smooth surface layer 39 (the film is in contact with the surface). The cleaning web 13a can relatively easily remove aggregates such as organic acids adhering to the surface).
[0083]
In addition, as shown with the broken line of FIG. 16, you may make it a small size film convey with a center reference | standard with respect to the heating drum 14, In this case, when a large size film is conveyed with a center reference | standard, a small size film will be conveyed. Although two passage traces relating to the film may affect the image, the passage traces on the surface of the heating drum 14 can be removed by operating the cleaning unit 13 of FIGS. Even if the large-size film is processed after the small-size film is processed, the possibility of affecting the image can be reduced. Thus, when it is not necessary to transport the film on one side, the film alignment mechanism in FIG. 12 may be omitted.
[0084]
In addition, when a relatively small size film is conveyed while being continuously heated many times on the heating drum 14, and then a relatively large size film is heated and conveyed, the elastic layer 38 on the outer peripheral surface of the heating drum 14 is conveyed. Since the smooth surface layer 39 made of a fluororesin can be used to prevent deterioration such as swelling of the elastic layer 38 during use of the heating drum 14, the film swelling trace in the vicinity of the small size line G1 is used as the film passage trace. It is possible to suppress the influence on the image that remains in the image.
[0085]
As described above, by providing the cleaning unit 13 with respect to the heating drum 14 having the smooth surface layer 39 on the surface of the elastic layer 38, even when the film is changed from the small size to the large size, the image of the film passing trace can be obtained. Can be greatly suppressed.
[0086]
Further, conventionally, in a heat development part for developing a silver salt photothermographic film using an organic solvent in particular, when the photothermographic film is developed, the surfactant on the film surface layer or the organic solvent from the emulsion layer or The organic acid is released from the film and attacks the elastic body such as silicon rubber on the surface layer of the heating drum, causing the elastic body to deteriorate, causing the elastic body to swell and wear, resulting in a stable finished image quality. In the present embodiment, the smooth surface layer 39 containing the fluororesin is formed on the elastic layer 38 to prevent the film surface layer from being developed when the photothermographic film is developed. By preventing the surface active agent or organic solvent or organic acid from the emulsion layer from attacking the high conductivity elastic body and preventing the elastic body from deteriorating over time, a stable finished image quality can be obtained. It becomes possible.
[0087]
Next, a guide member for first guiding the film F away from the heating drum 14 in FIG. 5 will be described. As shown in FIG. 5, a guide member 210 for separating the developed film F from the heating drum 14 and guiding it in the conveyance direction is located below the most downstream counter roller 16e between the heating drum 14 and the conveyance roller pair 144a. Is arranged. That is, the guide member 210 is arranged such that the guide surface 300 first guides the film F after the film F is conveyed between the heating drum 14 and the opposing roller 16 and separated from the outermost smooth surface layer 39. Has been.
[0088]
In the heat development apparatus 100 of FIG. 1, the film in the softened state after heat development on the guide surface 300 of the guide member 210 of FIG. 5 disposed close to the heating drum 14 is cooled and conveyed in FIG. 1 of the next step through the conveyance roller pair 144a. It is possible to guide to the portion 150 stably.
[0089]
In order to keep the gap between the leading end of the guide that guides the film separated from the heating drum to the cooling conveyance unit and the heating drum constant, it is conceivable to use an abutment roller system. Does not swell, etc., so that the diameter is constant at the longitudinal position of the drum, so that the gap between the guide tip and the heating drum can be reliably maintained constant, and there is no possibility of damaging the outer peripheral surface of the heating drum.
[0090]
Next, the cleaning operation in the heat developing apparatus 100 of FIGS. 1 to 15 will be described with reference to the flowchart of FIG.
[0091]
When image information including an image signal S and film size information is input from an external image signal output device 121 as shown in FIGS. 3 and 15 (S01), for example, a small size film is selected from the loading unit 11 or 12 and conveyed. In step S02, the exposure unit 120 exposes the film based on the image signal S to form a latent image (S03). The latent image is further conveyed to the heat development unit 130 and heated by the heating drum 14 to be developed. After being visualized (S04), it is transported while being cooled by the cooling transport unit 150 and discharged to the discharge unit 160 (S05).
[0092]
When the next image information is input (S06), it is determined whether there is a film size change from a small size to a large size based on the film size information (S07). The small film processing number n is increased to n + 1 (S08), and the process returns to step S02 to execute the same steps.
[0093]
Further, when the film size is changed from the small size to the large size (S07), when the small size film processing number n reaches a predetermined number because the small size film is continuously processed (S09), the film is conveyed. Is temporarily stopped, and the cleaning unit 13 is activated to clean the surface of the heating drum 14 (S10).
[0094]
Accordingly, one or two passing traces of the small size film as shown in FIG. 16 formed on the surface of the heating drum 14 can be removed by the cleaning web 13a of the cleaning unit 13 before the large size film is processed. Does not affect the image of large size film.
[0095]
When the cleaning in step S10 is completed, the process returns to step S02, and a large size film is selected from the loading unit 12 or 11 and conveyed, and the same steps are executed.
[0096]
If the number n of small-size film processes has not reached the predetermined number in step S09, it is not necessary to perform cleaning yet, and the process returns to step S02 without performing cleaning. The predetermined number n of the small-size film processing numbers can be set to an appropriate number by the control unit 152 of FIG.
[0097]
As described above, according to the thermal development apparatus of the present embodiment, the thermal development process is continuously performed on a small-sized film (such as six cuts having a width C of 8 or 10 inches in FIG. 16). Before the heat development process is performed by changing to a size film (half-cut, large angle, large partition, etc. with a width D of 14 inches), the surface of the heating drum 14 (the surface with which the film contacts) is cleaned. The influence on the image by the film passage trace formed by the continuous processing of the film can be reduced.
[0098]
As described above, the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made within the scope of the technical idea of the present invention. For example, in FIG. 5, the number of opposed rollers having a large heat storage capacity on the upstream side can be appropriately increased or decreased, and the wall thickness may be appropriately increased from a large-diameter tubular roller. Further, the material may be composed of a steel material other than stainless steel or an aluminum material. Further, the diameter of the opposing roller may be changed in three steps or more, or rollers having different diameters may be alternately arranged.
[0099]
13 and 14 is configured as a disposable type in which the cleaning web 13a is wound in one direction, but moves endlessly in one direction through the outer periphery of each of the rollers 13c, 13b, and 13d. Alternatively, an endless type may be configured.
[0100]
Further, the cleaning unit may be composed of a single cleaning roller as shown in FIG. That is, in the cleaning unit 13 of FIG. 18, a cleaning roller 13f having a width substantially the same as the width in the longitudinal direction of the heating drum 14 is connected to the arm 13g, and rotates together with the arm 13g around the rotation shaft 13i of the roller base 13h. It rotates in the moving direction u and in the opposite rotating direction u ′. When the cleaning roller 13f is rotated in the rotation direction u by an urging means (not shown) such as a spring and pressed against the surface of the heating drum 14, the surface of the heating drum 14 is rotated while being driven by the rotating heating drum 14. To clean. The cleaning roller 13 f is rotated in the rotation direction u ′ by a release means (not shown) for releasing the biasing means such as a spring and is separated from the surface of the heating drum 14 during non-cleaning.
[0101]
Further, the outer peripheral surface portion of the cleaning roller 13f shown in FIG. 18 is composed of an absorbent body made of a fiber material or a porous material, thereby efficiently absorbing deposits due to aggregation such as organic acid and MEK attached to the surface of the heating drum 14. It is possible to have heat resistance that can withstand the heat of the heating drum 14 and chemical resistance that can withstand deposits.
[0102]
【The invention's effect】
According to the present invention, when the photothermographic film is changed from a small size to a large size when executing the heat development process, it is possible to provide a heat development method and a heat development apparatus that have less influence on the image.
[Brief description of the drawings]
FIG. 1 is a front view showing a main part of a heat development apparatus according to the present embodiment.
FIG. 2 is a perspective view of the heat development apparatus of FIG. 1, showing a state in which a first loading unit is pulled out.
3 is a view schematically showing an exposure unit of the heat development apparatus of FIG. 1; FIG.
4 is a perspective view of a heat development unit 130 in FIG. 1. FIG.
5 is a cross-sectional view of the configuration of FIG. 4 taken along the line IV-IV and viewed in the direction of the arrows.
6 is a front view of the configuration of FIG.
FIG. 7 is a cross-sectional view of a film in the present embodiment, schematically showing a chemical reaction in the film during exposure with a laser beam.
8 is a cross-sectional view of a film in the present embodiment, and is a diagram schematically showing a chemical reaction in the film when the film on which the latent image as shown in FIG. 7 is heated is shown.
FIG. 9 is a side view schematically showing a transport unit provided in the first loading unit 11 of FIG. 2;
10 is a side cross-sectional view schematically showing a barrier bag removing unit in the first loading unit 11 of FIG. 2; FIG.
11 is a partially cutaway perspective view of a film package that can be loaded into the first and second loading sections of FIGS. 1 and 2. FIG.
12A is a view showing the storage tray portion of FIG. 2 including a film positioning mechanism, and is a cross-sectional view showing a state before the storage tray portion is broken in the width direction of the film and before alignment. FIG. It is sectional drawing (b) which shows the state after a) and alignment.
13 is an enlarged front view partially showing the cleaning unit and the heating drum in FIG. 1; FIG.
14 is a perspective view showing a cleaning unit provided in the heat development apparatus of FIG. 1. FIG. .
15 is a block diagram showing a control system of the cleaning unit 13 of FIGS. 1, 13, and 14. FIG.
FIG. 16 is a right side view of the heating drum of FIG. 1 (opposite rollers and the like are omitted).
FIG. 17 is a flowchart for explaining a cleaning operation in the heat developing apparatus 100 of FIGS.
18 is a front view similar to FIG. 13, showing a modification of the cleaning unit 13 of FIGS. 13 and 14. FIG.
[Explanation of symbols]
100 ... Thermal development apparatus
130 ... Thermal development section
11, 12 ... Loading section
13 ... Cleaning section
14 ... Heating drum
16 ... Opposite roller
38 ... Elastic layer
39 ... smooth surface layer (surface layer)
120... Exposure part
130 ... Thermal development section
152... Control unit
F ... Film (Photothermographic film)

Claims (4)

A step of selecting and conveying a size from a plurality of pre-loaded sheet-like photothermographic films based on film size information previously attached to the input image information ;
Exposing the conveyed photothermographic film to form a latent image;
Heating and visualizing the photothermographic film having the latent image formed thereon by a heating unit,
A heat developing method, comprising: cleaning a film contact surface of the heating unit when the size of a photothermographic film selected based on the film size information is changed from a small size to a large size. A heat development apparatus for forming an image on a sheet-like heat development photosensitive film based on input image information,
A plurality of film mounting means each capable of loading a sheet-like photothermographic film of different sizes;
Conveying means for conveying the photothermographic film on the film placing means;
Exposure means for forming a latent image on the conveyed photothermographic film;
A heat developing means having a heating portion for visualizing the heat developable photosensitive film on which the latent image is formed;
Cleaning means for cleaning the film contact surface of the heating unit ;
Based on the film size information preliminarily attached to the input image information, the sheet-like photothermographic film loaded in any of the plurality of film mounting means is selected and conveyed to the conveying means, A control unit that controls the cleaning means to clean the film contact surface of the heating unit when it is determined that the selected photothermographic film is changed from a small size to a large size based on the film size information ; , thermal developing apparatus is characterized in that it comprises.   3. The heat developing apparatus according to claim 2, wherein the cleaning unit is configured to be pressed against the film contact surface during cleaning and to be separated during non-cleaning. When the control unit counts the number of small-size film processed on the small-size film continuously based on the film size information, and determines that the selected photothermographic film has been changed from a small size to a large size The heat developing apparatus according to claim 2 , wherein control is performed so that the film contact surface of the heating unit is cleaned when the number of processed small-size films reaches a predetermined number .

Images