JP2000292901A - Heat developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developing device where unevenness and developing irregulality in heat developing material can be decreased. SOLUTION: In this heat developing device, a drum 14 where a film is carried and heated, a roll 16 that can be rotated guiding the film to the drum by having it energized and a driving source are provided. The roll is rotated by having driving force of the driving source transmitted to the roll. A surface layer of the drum is an elastic body with hardness of 30 to 80 deg. and thickness of 0.3 to 2 mm. Furthermore, a member with a great moment of inertia for rotation can be installed to the roll. The roll can work interlockingly with the rotation inertia member that has a greater moment of inertia for rotation than the moment of inertia for rotation of the roll.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat developing apparatus which heats and thermally develops a silver halide photosensitive heat developing material after exposing the same based on image information.

[0002]

2. Description of the Related Art A heating member (drum) for heating while carrying a photothermographic material while holding it on a holding surface, and urging and guiding the photosensitive material held by the heating member to the heating member. A thermal developing apparatus having a rotatable guide member (roller) for thermally developing the photosensitive material is known as, for example, DRYVIEW (trademark) manufactured by Imation Corporation.

In such a conventional thermal developing apparatus,
In order to suppress generation of pressure fogging and indentation during thermal development, it is preferable that the urging force on the photosensitive material by the guide member is weak.

[0004]

However, the guide member (roller) of such a prior art heat developing apparatus is rotated by receiving a driving force from the photosensitive material being conveyed. If you reduce the bias,
The guide member for guiding the photosensitive material cannot receive sufficient conveying force from the photosensitive material, the guide member substantially stops, and a specific area of the guide member is cooled by applying heat to the photosensitive material. Could be

Accordingly, the temperature history of the photosensitive material differs between when the region of the guide member contacts the photosensitive material and when the region other than that region of the guide member contacts the photosensitive material, and uneven development occurs on the photosensitive material. Can occur.

As described above, in a heat developing apparatus that heats a photosensitive material while holding it by a heating member controlled to a predetermined heat development temperature and a guide member facing the heating member, the heating member can stably convert the photosensitive material to the photosensitive material. It is necessary to supply heat uniformly. Therefore, it is necessary to convey the photosensitive material held and conveyed by the heating member and the guide member with as little speed unevenness as possible and stably. For this purpose, a means for increasing the friction coefficient of the heating member and the guide member (increase the surface roughness), which is a conveying means, and for increasing the pressing force are usually performed, but when the surface roughness is increased, unevenness of the surface is increased. The image is transferred to the heat developing member or density unevenness occurs. Further, if the pressing force is simply increased, the thermal developing member is easily affected by pitch unevenness of gears and the like, and uneven density and unevenness are generated.

The present invention has been made in view of these problems, and has as its object to reduce unevenness and uneven development.

[0008]

In order to achieve the above object, the present invention provides a heating member for heating a photothermographic material while holding it on a holding surface, and heating the photothermographic material. A heat-developing device for thermally developing the photosensitive material, comprising: a driving source; and a driving force of the driving source, the driving force being transmitted to the guiding member. And a driving force transmitting mechanism for rotating the guide member, wherein the surface layer of the heating member is an elastic body having a hardness of 30 to 80 ° and a thickness of 0.3 to 2 mm.

According to the present invention, since the guide member is rotated by receiving the driving force from the driving force transmitting mechanism, the guide member rotates stably, so that the speed unevenness can be prevented, and only a specific area of the guide member is cooled. Is less likely to occur, and the above-described uneven development is less likely to occur. However, it has been found that if this is simply done, if the manufacturing accuracy of the heating member and the guide member is not sufficient, density unevenness occurs at regular intervals, and it is conspicuous. In the case where the guide member rotates, such density unevenness occurs irregularly, so that it is inconspicuous. When the surface layer of the heating member is hard and has a hardness of more than 80 °, unevenness in concentration tends to occur due to the influence of the manufacturing accuracy of the heating member and the guide member. The manufacturing accuracy of the guide member is less likely to be affected, and density unevenness is less likely to occur. The surface layer is soft and hardness is 30 °
If less than, the elastic body itself is liable to be deteriorated, and the influence of the manufacturing accuracy of the heating member and the guide member is likely to be affected.However, since the hardness is 30 ° or more, wear resistance can be ensured,
Such deterioration hardly occurs, the durability is improved, and the manufacturing accuracy of the heating member and the guide member is hardly affected, and the density unevenness is hardly generated. Further, if the thickness of the surface layer exceeds 2 mm, the heat conduction to the surface is reduced, and the response is reduced when the temperature is controlled, and the density unevenness is apt to occur, but the thickness is 2 mm or less. Therefore, the responsiveness is improved, the temperature is easily controlled, and the density unevenness is less likely to occur. Further, when the thickness of the surface layer is less than 0.3 mm, the temperature rises sharply and the photosensitive material is liable to bleed, and the influence of the manufacturing accuracy of the heating member and the guide member tends to be increased. , 0.3 mm or more, it is difficult for fog to occur without a sharp rise in temperature, and it is difficult to affect the manufacturing accuracy of the heating member and the guide member,
Concentration unevenness is unlikely to occur.

Another object of the present invention is to provide a heating member which heats the photothermographic material while transporting it while holding the photothermographic material on a holding surface;
A rotatable guide member for urging the photosensitive material held by the heating member against the heating member to guide the photosensitive material, wherein a rotational inertia of the guide member is provided. A member for increasing the moment is provided on the guide member, and the surface layer of the heating member has a hardness of 30 to 80.
And an elastic body having a thickness of 0.3 to 2 mm.

According to the present invention, since the guide member is provided with a member having a large rotational moment of inertia, the guide member is hard to stop and stably rotates, so that it is possible to prevent uneven speed and to specify the guide member. It is unlikely that only the region is cooled, and the above-described uneven development is unlikely to occur.
Since the hardness and the thickness of the surface layer of the heating member are defined in the same manner as described above, the same effects can be obtained.

Still another aspect of the present invention is a heating member for heating the photothermographic material while transporting it while holding the photothermographic material on a holding surface, and urging the photosensitive material held by the heating member against the heating member. A rotatable guide member that guides the photosensitive material, and a heat development device that thermally develops the photosensitive material, wherein a rotary inertia member having a rotary inertia moment larger than the rotary inertia moment of the guide member interlocked with the guide member is provided. Wherein the surface layer of the heating member is an elastic body having a hardness of 30 to 80 ° and a thickness of 0.3 to 2 mm. According to the present invention, since the guide member is interlocked with the rotational inertia member having a larger rotational inertia moment than the rotational inertia moment of the guide member, the guide member rotates stably, so that it is possible to prevent speed unevenness, and only a specific area of the guide member Is less likely to be cooled, and the above-described uneven development is less likely to occur. Since the hardness and the thickness of the surface layer of the heating member are defined in the same manner as described above, the same effects can be obtained.

When the surface roughness of the elastic body of the surface layer is 1.6 μm or less, fine concentration unevenness and unevenness are unlikely to occur. Further, since the guide member is made of a metal material, the manufacturing accuracy of the guide member can be ignored.
This metal material is iron, aluminum, their alloys,
Or stainless steel.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments and examples of the present invention, which are examples of the present invention, will be described. Therefore, the meaning of the terms of the invention and the invention itself should not be construed as being limited by the description of the embodiments and examples of the invention, and it is needless to say that the invention can be appropriately changed / improved. Embodiment FIG. 1 is a front view of a heat developing apparatus of the present embodiment, and FIG.
FIG. 2 is a left side view of the heat developing device. Thermal developing device 10
Reference numeral 0 denotes a feeding unit 110 that feeds the film F, which is a sheet-like heat development material, one by one, an exposure unit 120 that exposes the fed film F, and a thermal development that develops the exposed film F. Unit 130. Hereinafter, the image forming apparatus of the present embodiment will be described with reference to the drawings.

In FIG. 2, the feeding section 110 is provided with trays T for accommodating a plurality of deposited films F in two upper and lower stages. Above the front end side of each tray T, a suction unit 1 that moves up and down by sucking the front end of the film F
11 are provided. In the vicinity of the suction unit 111, a pair of feed rollers 1 for feeding the film F supplied by the suction unit 111 in the direction of the arrow (1) (horizontal direction).
12 are provided. Further, the suction unit 111 can move back and forth and feed the film F, which has been sucked, to the feeding roller pair 1.
12 can be carried. Then, the feed roller pair 112
Are provided with a plurality of transport roller pairs 141 for transporting the film F fed in the vertical direction. The film F is transported by these transport roller pairs 141 in the direction (downward) shown by the arrow (2) in FIG.

A transport direction changing unit 145 is provided below the thermal developing device 100. This transport direction converter 14
5 is a transport roller pair 141 as shown in FIGS.
As a result, the film F conveyed vertically downward as shown by the arrow (2) in FIG. 2 is conveyed in the horizontal direction as shown by the arrow (3), and then the conveyance direction is perpendicular to the arrow (3) from the arrow (4). Then, the film F whose transport direction has been changed and transported is transported upward in the vertical direction indicated by the arrow (5) in FIG.

Then, as shown in FIG. 1, the film F conveyed from the conveyance direction changing unit 145 is moved by an arrow (6) in FIG.
Plural transport roller pairs 14 transported vertically upward as indicated by
2 is provided, and the film F is transported from the left side surface of the heat developing device 100 upward in the vertical direction indicated by an arrow (6) in FIG.

In the course of transporting the film F upward in the vertical direction, the exposure unit 120 moves the photosensitive surface of the film F to the infrared region 780 to 860.
Scanning exposure is performed with laser light in the range of nm (810 nm in the present embodiment) to form a latent image corresponding to an exposure image signal.

A heat developing section 130 is provided on the upper part of the heat developing apparatus 100. In the vicinity of the drum 14 of the heat developing section 130, a pair of conveying rollers 142 is provided vertically upward as shown by an arrow (6) in FIG. A supply roller pair 143 for supplying the film F conveyed to the drum 14 to the drum 14 is provided.

The film F is supplied to the drum 14 at random timing depending on the situation.

It is to be noted that the supply may be performed at a suitable timing instead of the supply at a random timing. As an example of supplying at a timing, the supply roller pair 143 is used.
However, it may stop until the next supplied position on the circumference of the drum 14 reaches the predetermined rotation position, and rotate when the next supplied position on the circumference of the drum 14 reaches the predetermined rotation position. good. That is, the film F may be supplied to a predetermined supply position of the drum 14 by controlling the rotation of the supply roller pair 143.

The drum 14 of the heat developing unit 130 heats the film F while rotating in the direction indicated by the arrow (7) in FIG. 1 with the film F and the outer peripheral surface of the drum 14 in close contact with each other. And heat develop. That is, the film F
Is formed into a visible image. Then, the drum 1 of FIG.
The film F is separated from the drum 14 when the film F is rotated to the right with respect to the film 4. A plurality of transport roller pairs 144 are provided on the right side of the thermal developing unit 130, and while transporting the film F separated from the drum 14 obliquely downward to the right as shown by an arrow (8) in FIG. Cooling. Then, the transport roller pair 144 transports the cooled film F while the densitometer 1
18 measures the concentration of the film F. Thereafter, the plurality of transport roller pairs 144 are moved to the film F separated from the drum 14.
Is transported in the horizontal direction as shown by the arrow (9) in FIG. 1, and is discharged to a discharge tray 160 provided at the upper right portion of the heat developing device 100 so that it can be taken out from the upper portion of the heat developing device 100.

FIG. 3 is a schematic diagram showing the configuration of the exposure unit 120. The exposure unit 120 deflects the laser light L, the intensity of which has been modulated based on the digital image signal S, by the rotating polygon mirror 113 to perform main scanning on the film F, and also performs main scanning of the film F with respect to the laser light L. The sub-scan is performed by relatively moving in a direction substantially perpendicular to the direction, and a latent image is formed on the film F using the laser light L.

The thermal developing device 100 receives the digital image signal S transmitted from the image transmitting device 121 such as a radiation CT device or a scanner via the image I / F 122, and
23. The modulation unit 123 sends the analog-converted exposure image signal to the driver 124, and
Reference numeral 4 denotes a laser light source unit 125 according to the transmitted exposure image signal.
Is controlled to emit laser light.

The laser light L emitted from the laser light source unit 125 is converted into parallel light by the condenser lens 126, and is converged by the cylindrical lens 115 only in one direction (up and down in this embodiment). Is incident on the rotating polygon mirror 113 which rotates in the rotation direction shown in FIG. The rotary polygon mirror 113 reflects and deflects the laser light L in the main scanning direction. The deflected laser light L passes through an fθ lens 114 including a cylindrical lens formed by combining four lenses, and then is focused on an optical path. On the surface to be scanned of the film F, which is reflected by the mirror 116 extending in the scanning direction and conveyed (sub-scanned) by the conveying device 142 in the direction of the arrow Y,
Main scanning is repeatedly performed in the arrow X direction. In this way,
The laser light L scans the entire surface to be scanned on the film F.

The cylindrical lens of the fθ lens 114 transmits the incident laser beam L onto the surface of the film F to be scanned.
Converge only in the sub-scanning direction. Thus, the main exposure unit 1
In FIG. 20, an fθ lens 114 including a cylindrical lens and a mirror 116 are provided, and the laser light L
Are once converged only in the sub-scanning direction on the rotating polygon mirror 113. Therefore, even if the rotating polygon mirror 113 is tilted or deflected, the laser light L Is not shifted in the sub-scanning direction, so that scanning lines at equal pitches can be formed. The rotary polygon mirror 113 has an advantage that it is superior in scanning stability 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.

FIGS. 4 to 6 are views showing the structure 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. FIG. 6 is a cross-sectional view of the configuration of FIG. 4 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 as viewed from the front.

The heat developing section 130 heat develops the film F by maintaining the film F at a temperature equal to or higher than a predetermined minimum heat development temperature for a predetermined heat development time. That is, the latent image formed on the film F is formed as a visible image.
Here, the minimum thermal development temperature is a minimum temperature at which the latent image formed on the film F starts to be developed by a thermal reaction, and is around 110 ° C. in the film F of the present embodiment. On the other hand, the term "thermal development time" refers to the time during which the latent image of the film F must be maintained at a temperature equal to or higher than the minimum thermal development temperature in order to develop the film with desired development characteristics. In this embodiment,
The film F is set at 40 ° C., which is the environmental temperature at which the apparatus can be installed.
In the following, it is preferred that the material is not substantially thermally developed.

The heat developing section 130 has a drum 14 which can heat the film F while holding it on the outer peripheral surface. The drum 14 is an example of the heating member of the present invention, and the film F
Is maintained at a temperature equal to or higher than a predetermined minimum heat development temperature for a predetermined heat development time, thereby forming the formed latent image on the film F as a visible image.

In the present embodiment, the heat developing section 130 is incorporated in the heat developing apparatus 100 together with the exposure section 120, but may be an apparatus independent of the exposure section 120. In such a case, the exposing unit 120 may be
It is preferable that there is a transport unit that transports the film F to the side.

Outside the drum 14 is a small-diameter roller 16.
Are provided. These 20 rollers 16 are an example of the guide member of the present invention, and are opposed to the drum 14 so that the rotation axis thereof is parallel to the rotation axis of the drum 14, and the circumferential direction of the drum 14. Are arranged at equal intervals. At both ends of the drum 14, three guide brackets 21 supported by the frame 18 are provided on each side. In addition, by combining the guide brackets 21, opposed C-shaped shapes are formed at both ends of the drum 14.

Each guide bracket 21 has nine elongated holes 42 extending in the radial direction. The shafts 40 provided at both ends of the roller 16 protrude from the long holes 42. One end of a coil spring 28 is attached to each of the shafts 40, and the other end of the coil spring 28 is attached near the inner edge of the guide bracket 21. Therefore, each roller 16 is urged to the outer periphery of the drum 14 by a predetermined force based on the urging force of the coil spring 28. When the film F enters between the outer periphery of the drum 14 and the roller 16, the film F is pressed against the outer peripheral surface of the drum 14 by the predetermined force, thereby uniformly heating the film F over the entire surface.

The shaft 2 coaxially connected to the drum 14
The reference numeral 2 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 23 a is formed on a rotating shaft 23 of a stepping motor 26 which is disposed below the shaft 22 and attached to the end member 20. On the other hand, a gear 22a is also formed on the shaft 22. The rotation of the step motor is transmitted to the shaft 22 via a gear 23a and a timing belt (belt on which the gear is engraved) 25 around which the gear 22a is wound.
The drum 14 rotates. The transmission of power from the rotating shaft 23 to the shaft 22 is performed by using a timing belt instead of a timing belt.
A chain or a gear train may be used.

As shown in FIG. 5, in the present embodiment, the roller 16
It is provided over a range of degrees. Two reinforcing members 30 (FIG. 5) connect the end members 20 of the frame 18 and additionally support the end members 20.

On the inner periphery of the drum 14, a plate-like heater 32 is provided.
Are mounted over the entire circumference to heat the outer circumference of the drum 14 under the control of the electronic device 34 shown in FIG. Power is supplied to the heater 32 via a slip ring assembly 35 connected to an electronic device 34.

In the present embodiment, the drum 14 is formed in a rotatable cylindrical shape in order to make the structure of the heat developing apparatus 100 compact, but another structure is used as a means for heating the film F. Is also good. For example, it is conceivable that the film F is placed on a belt conveyor provided with a heater, and the film F is heated while being conveyed by the belt conveyor.

As shown in FIG. 5, the drum 14 includes a support tube 36 made of aluminum, which is a metal support member, and a flexible surface layer (elastic layer) 38 attached outside the support tube 36. ing. The surface layer 38 may be indirectly attached to the support tube 36. The support tube 36 according to the present embodiment has a length of 45.7.
cm, the wall thickness is 0.64 cm, and the outer diameter is 16 cm.

On the other hand, the thickness unevenness of the support tube 36 is as follows.
For example, it is preferable to keep it within 4%. Further, the surface layer 38 has a sufficiently smooth surface to increase the degree of adhesion to the film F to be heated,
The average surface roughness Ra is desirably smaller than 1.6 μm. When the average surface roughness (Ra) of the surface layer 38 is 1.6 μm or less, fine density unevenness and unevenness hardly occur in the film, which is preferable.

However, the surface roughness Ra of the surface layer 38
In order to prevent the film F from sticking to the drum 14, it is preferable that the thickness be 0.3 μm or more. If the surface roughness Ra is 0.3 μm or more, a gas, particularly a volatile material, is easily discharged from between the surface layer 38 and the film F. In particular, when the surface layer contains an additive for increasing thermal conductivity and silicon rubber, the surface roughness Ra
In order to prevent the film F from sticking to the drum 14, it is preferable that the thickness be 0.3 μm or more.

The surface layer 38 has a sufficient thermal conductivity of 0.3 W / m / K or more, so that the surface temperature of the outer peripheral surface of the drum 14 is kept uniform. In the present embodiment, the thermal conductivity of the surface layer 38 is 0.4 W / m /
K or more.

If the surface layer 38 is hard and has a hardness of more than 80 °, the density of the drum 14 and the rollers 16 is likely to be uneven due to the influence of the manufacturing accuracy. The influence of the manufacturing accuracy of the roller 16 and the roller 16 is less likely to occur, and uneven density is less likely to occur. The surface layer 38
Is soft and has a hardness of less than 30 °, the elastic body itself is liable to be deteriorated, and the production accuracy of the drum 14 and the rollers 16 is apt to be affected. However, since the hardness is 30 ° or more, abrasion resistance is secured. Such deterioration is unlikely to occur, and the durability is improved. In addition, the influence of the manufacturing accuracy of the drum 14 and the rollers 16 is less likely to occur, and density unevenness is less likely to occur. According to the surface layer 38 of the present embodiment, the film 16 is applied to the drum 14 by the roller 16 without sacrificing wear resistance.
It comes to adhere more surely. The surface layer 38
It is measured by a durometer, and in the present embodiment, the hardness is 30 ° or more and 55 ° or less in Shore A hardness measured by the durometer.

When the thickness of the surface layer exceeds 2 mm,
Since the heat conduction to the surface is reduced, the responsiveness is reduced when the temperature is controlled, and the density unevenness is apt to occur. However, since the thickness is 2 mm or less, the responsiveness is improved, and the temperature can be easily controlled. Unevenness is unlikely to occur. Further, when the thickness of the surface layer is less than 0.3 mm, the temperature rises sharply and the photosensitive material is liable to bleed, and the influence of the manufacturing accuracy of the heating member and the guide member tends to be increased. , 0.3 mm or more, it is difficult for fog to occur without a sharp rise in temperature, and it is difficult to affect the manufacturing accuracy of the heating member and the guide member,
Concentration unevenness is unlikely to occur. In the present embodiment, the thickness of the surface layer is 0.5 mm.

The surface layer 38 is preferably formed of a material containing an additive for increasing the thermal conductivity and silicon rubber, whereby the pressing performance against the film F and the film F Has an advantage that the film F is easily separated from the film F and is chemically inert.

The variation in the thickness of the surface layer 38 is preferably 20% or less (particularly 10% or less) on the surface region. In the present embodiment, it is suppressed to 5% or less.

In this embodiment, an aluminum tube having an outer diameter of 1 to 2 cm and a thickness of 2 mm is used as the roller 16. Since the roller 16 is hollow, the suppression of heat conduction is assisted, whereby the influence of the heat of the roller 16 during development can be eliminated as much as possible. The roller 16 may be formed of a solid or filled cylindrical member, instead of being hollow.

In this embodiment, the surface substrate of the roller 16 is also made of aluminum, and has a thermal conductivity of 200 W / m / K or more. As a result, the roller 16
Does not receive sufficient conveying force from the film F, the roller 16 is substantially stopped, and even if only a specific area of the roller 16 is cooled, heat is rapidly transmitted from the surroundings.
The temperature of only the specific area of the roller 16 is prevented from lowering, and the occurrence of development unevenness is suppressed.

As described above, the urging force of the coil spring 28 is used to reduce the pressing force of the roller 16 so that the film F can be brought into close contact with the outer peripheral surface of the drum 14 and receive sufficient heat transfer. Care must be taken when choosing the value, as it is a decision. If the urging force of the coil spring 28 is too small, heat may be unevenly transmitted to the film F, so that image development may be incomplete. Therefore, the urging force from the roller 16 per 1 cm width of the film F is preferably 3 g or more (particularly 5 g or more). If the urging force from the roller 16 per 1 cm width of the film F is less than 14 g, there is a possibility that the roller 16 does not wrap around the drum 14. In particular, if the urging force is 7 g or less, no rotation occurs. In such a case, the film F rotates and moves together with the drum 14,
When the stationary roller 16 is in contact with the film F, the film F cools only the contact area of the stationary roller 16, the temperature of the contact area of the roller 16 continues to decrease, and the temperature history of the film F is stored for each area. In addition to the difference, even if the roller 16 rotates with the film F again, a temperature difference occurs between the cooled contact area of the roller 16 and an area other than the contact area. The temperature history of the heat-developable material differs between the area of the film F in contact with the contact area and the area of the film F in which the area other than the contact area of the roller 16 contacts, resulting in uneven development of the heat-developable material.

Next, the reason why the roller 16 slips with respect to the film F or stops rotating will be described. The roller 16 is driven (rotated) by the frictional force acting between the roller 16 and the film F, and the torque for rotating the roller 16 is:
It depends on the Niff angle force N of both. Here, depending on the resistance R of the roller 16 by a shaft supporting method (for example, a sliding bearing) and the friction coefficient μ between the film F and the roller 16, even if the nip pressure N is increased, μN <R, and the roller 16 does not rotate. As a result, the film F may slip.

Therefore, in order to suppress the occurrence of such slip and stoppage of rotation, it is conceivable to perform a treatment for increasing the friction coefficient on the surface of the film F. The number of processing steps in manufacturing increases, and the cost increases. Therefore, one problem is to make the roller 16 rotate smoothly without increasing the number of processing steps of the film F.

Therefore, in the present embodiment, such a problem is solved as follows. FIG. 9 is a perspective view showing the ends of the drum 14 and the roller 16. FIG. 10 is a diagram in which one of the drum 14 and the roller 16 in FIG. 9 is viewed in the arrow X direction. In FIG. 9, only five of the 20 rollers 16 are shown to avoid complicating the drawing, but all the rollers 16 have the same configuration.

9 and 10, gear teeth 16a are provided at both ends of each roller 16, and gear teeth 14a are provided at both ends of the drum 14. These gear teeth 16a and gear teeth 14a mesh with each other. The roller 16 is driven by the drum 14 through the gear teeth. Even if the roller 16 receives no driving force from the film F, the roller 16 is rotated by the driving force of the roller 16 to prevent the roller 16 from stopping. Can be prevented.

FIG. 11A is a diagram showing a first modification of the above-described combination of gear teeth. FIG. 11 (a)
In the first modified example shown in FIG. 1, rubber members 16c are coated on the outer periphery of both ends of each roller 16 and the drum 14
A ring member 14b formed of, for example, sponge and having excellent elastic deformation properties is fitted on the outer periphery of both ends of the. Thus, when the film F is not inserted or when it is inserted, the ring member 14b is deformed, so that the rubber member 16c and the ring member 14b are pressed with substantially the same force, and substantially the same frictional force is generated. Since the coefficient of static friction and the coefficient of kinetic friction between the rubber member 16c and the ring member 14b are very high, this frictional force is strong.

Therefore, when the drum 14 is rotated by the power of the stepping motor 26, the frictional force generated between the ring member 14b and the rubber member 16a causes the roller 1 to rotate.
6 is also driven. At this time, even when the film F is inserted between the drum 14 and the roller 16, since the roller 16 is given a sufficient driving force, the roller 16 stops due to the resistance caused by the insertion of the film F. And uneven development can be suppressed.

FIG. 11B is a diagram showing a second modification. In the modification shown in FIG.
The outer periphery of both ends of each roller 4 is covered with a rubber member 14c, and the outer periphery of both ends of each roller 16 is provided with a ring member 16b formed of, for example, a sponge having excellent elastic deformability.
Are fitted and fitted. Thus, when the film F is not inserted or inserted, the ring member 16b is deformed, so that the rubber member 14c and the ring member 16b are pressed with substantially the same force, and substantially the same frictional force is generated. Since the coefficient of static friction and the coefficient of kinetic friction between the rubber member 14c and the ring member 16b are very high, the frictional force is strong.

Therefore, when the drum 14 is rotated by the power of the stepping motor 26, the frictional force generated between the ring member 16b and the rubber member 14a causes the roller 1 to rotate.
6 is also driven. At this time, even when the film F is inserted between the drum 14 and the roller 16, since the roller 16 is given a sufficient driving force, the roller 16 stops due to the resistance caused by the insertion of the film F. And uneven development can be suppressed.

FIG. 12 is a diagram showing a third modification.
FIG. 3 is a diagram illustrating a part of a drum and a roller when viewed in an axial direction. In FIG. 12, only four rollers 16 are shown to avoid complicating the drawing, but all the rollers 16 have the same configuration.

Each roller 16 is provided with a steel ring 16c having a large rotational moment of inertia at a position beyond both ends of the drum 14 in the direction of the rotation axis of the drum 14.
When the drum 14 is rotated by the power of the stepping motor 26, the film F
6, the roller 16 is also driven by the frictional force acting on the film F. And the ring 16
c, the rotational moment of inertia is large.
Starts rotating, the roller 16 continues to rotate like a top, even if it receives resistance for some reason, the possibility of stopping is reduced, and uneven development can be suppressed. Also, since the slip between the film F and the roller 16 can be suppressed,
It is also possible to prevent the film from being scratched.

FIG. 13 is a diagram showing a fourth modification.
FIG. 3 is a diagram illustrating a part of a drum and a roller when viewed in an axial direction. Note that FIG. 13 also shows only four rollers 16 to avoid complicating the drawing, but all the rollers 16 have the same configuration.

Each roller 16 is provided with a roller gear 16 d at a position beyond both ends of the drum 14 in the direction of the rotation axis of the drum 14.
Is attached. The roller gear 16d meshes with an intermediate gear 16e, and the intermediate gear 16e meshes with a large gear 16f formed separately but coaxially with the drum 14. The large gear 16f is a flywheel made of steel and having a large rotational moment of inertia.

When the drum 14 is rotated by the power of the stepping motor 26, the film F
When entering between the roller 4 and the roller 16, the roller 16 is also driven by the frictional force acting between the roller 4 and the film F. Since the rotational moment of inertia of the large gear 16f connected to each roller 16 is large, once the large gear 16f starts rotating, the large gear 16f continues rotating even if it receives resistance for some reason. The roller 16f keeps rotating, and accordingly the roller 16 keeps rotating, so that stoppage can be suppressed, and development unevenness can be suppressed. Further, since the gear ratio is selected as shown in FIG. 13 so that the large gear 16f rotates at a high speed with respect to the drum 16, the performance as a flywheel is easily exerted.

FIG. 14 is a diagram showing a fifth modification.
FIG. 3 is a diagram illustrating a part of a drum and a roller when viewed in an axial direction. In FIG. 14, only four rollers 16 are shown to avoid complicating the drawing, but all the rollers 16 have the same configuration.

Roller gear 16 provided on each roller 16
g is the intermediate gear 16 with respect to the adjacent roller gear 16g.
h so as to be able to transmit power. In FIG. 14, the lowermost intermediate gear 16h meshes with a drive gear 16i, and the drive gear 16i meshes with a pinion gear 16j attached to the rotation shaft of the motor M. The motor M starts rotating in response to the rotation of the drum 14, and its rotation speed is adjusted so that the peripheral speed of the drum 14 matches the peripheral speed of the roller 16. .

When the drum 14 is rotated by the power of the stepping motor 26, the film F
Even if the roller 16 enters between the roller 4 and the roller 16, each roller 16 rotates based on the power of the motor M. Therefore, even if the roller 16 receives resistance for some reason, the roller 16 continues to rotate by the power and does not stop. Unevenness can be suppressed.

The four rollers 16 are rotatably supported by the housing B. The housing B is configured to be pivotable about a shaft of the motor M so that the housing B can be opened and closed with respect to the drum 14.

If the film F is jammed between the roller 16 and the drum 14 for some reason, the housing B is moved to the position shown by the dotted line in FIG. F can be easily taken out.

FIG. 15 is a view showing a sixth modification.
FIG. 3 is a diagram illustrating a part of a drum and a roller when viewed in an axial direction. In FIG. 15, four rollers 16 are shown as one unit to avoid complicating the drawing, but the other rollers 16 have the same configuration.

The four rollers 16 are rotatably supported by the housing B. The housing B is configured to be pivotable about one roller 16 so as to be able to open and close with respect to the drum 14. The rollers 16 are linked by a chain or a timing belt 16k so that they can rotate in synchronization with each other. The chain or the timing belt 16k is supplied with power from the motor M via the chain or the timing belt 16m. The motor M starts rotating in response to the rotation of the drum 14, and its rotation speed is adjusted so that the peripheral speed of the drum 14 matches the peripheral speed of the roller 16. .

When the drum 14 is rotated by the power of the stepping motor 26, the film F
Even if the roller enters between the roller 4 and the roller 16, each roller 16
Since it rotates based on the power of the motor M supplied via the chain or the timing belts 16k and 16m,
Even if resistance is received for some reason, the roller 16 keeps rotating and does not stop, so that development unevenness can be suppressed.

If the film F is jammed between the roller 16 and the drum 14 for some reason, the housing B is moved to the position shown by the dotted line in FIG. F can be easily taken out.

As a seventh and eighth modified examples, the roller 1
Surface treatment may be applied to the surface of No. 6 so that the coefficient of static friction between the heat-developable material and the roller 16 side surface at the heat development temperature is 2.0 or more, or the dynamic friction coefficient is 1.0 or more. Thereby, even if the urging force of the roller 16 to the film F is weak, the roller 16 can be rotated, and unevenness in thermal development can be suppressed.

As described above, since the structure for smoothly rotating the roller 16 is provided, the urging force of the coil spring 28 can be reduced to such an extent that the roller 16 does not generate an indentation or the like on the film F.

Accordingly, the urging force from the roller 16 per 1 cm width of the film F is set to 200 g or less (especially 100 g
Below). In the present embodiment, this force is between 5 and 7 g per 1 cm in the width direction of the film F.

In addition, when each coil spring 28 is used for the roller 16 provided around the cylindrical drum 14, the urging force of each coil spring 28 is applied in consideration of the gravity acting on each roller 16. It is good to decide. For example, the coil spring 28 that urges the roller 16 located above the drum 14 responds more to the weight of the roller 16 than the other coil spring 28 that urges the roller 16 at the bottom of the drum 14. By setting the urging force to be smaller than the above, substantially the same surface pressure can be applied to the entire film F.

As shown in FIGS. 4 to 6, 20 rollers 1
6 are provided over 171 degrees in the direction of rotation of the drum 14, and each space is separated from the center by 9 degrees from the center. In this configuration, the diameter of the drum 14 is 15 cm to 30 cm, and the diameter of the roller 16 is 1 to 2 cm.
cm, the thickness of the base is 0.1-0.2 mm
Film, for example, a polyester film having a base thickness of 0.18 mm, such as a film in which the film F is relatively hard, and a film having a base thickness of 0.10 mm, such as a polyester film. It is effective for those having lower hardness.

The heater 32 is mounted on the inner circumference of the drum 14 to heat the outer circumference of the drum 14. As the heater 32 for heating the drum 14, an etched resistive foil heater can be used.

The electronic device 34 rotates together with the drum 14 and can adjust the power supplied to the heater 32 according to the temperature detected by the temperature sensor arranged on the drum 14. With the heater 32 and the electronic device 34, the heat development temperature of the film F is
The temperature of the outer surface of the drum 14 is adjusted. In the present embodiment, the heater 14 and the electronic device 34
Can be heated to a temperature of 60C to 160C.

Here, it is preferable that the temperature unevenness on the outer surface of the drum 14 be maintained within 2.0 ° C. (in particular, within 1.0 ° C.) by the heater 32 and the electronic device 34. In the present embodiment, the temperature is maintained within 0.5 ° C.

The undeveloped film F supplied from the supply roller pair 143
And the nip portion 50 formed by the roller 16 on the most upstream side. Next, the film F rotates together with the drum 14. At this time, the film F is urged against the drum 14 by the roller 16 and is brought into contact with the outer periphery of the drum 14 for a predetermined time during the rotation.

Since the drum 14 moves at substantially the same speed as the film F to be developed, the possibility that the surface of the film F is scratched (damaged or damaged) is low, so that a high quality image can be secured. . After being transported between the drum 14 and the roller 16, the developed film F is guided to the nip 52 formed by the roller 16 and the drum 14 located at the most downstream side, and the peeling member 53 is developed. Part 1
The film F is peeled from the drum 14
From the cooling device 150
Guide in the direction of A. As a result, the risk of scratching (damage) is reduced, and the risk of surface wear is also reduced.
The developed film F is gradually cooled in the cooling device 150A first, and then rapidly cooled.

For example, in the embodiment, the developing unit 130 develops various films F such as a 0.178 mm polyester base layer coated with a photosensitive heat-developable emulsion containing the infrared-sensitive silver halide described in the embodiment. It is composed of The drum 14 is maintained at a temperature of 115 ° C. to 138 ° C., for example, at 124 ° C.
For about 15 seconds, which is a predetermined time, at a rotational speed such that it is held in contact with its outer peripheral surface. At the predetermined time and the temperature, the film F can be raised to a temperature of 124 ° C.

FIG. 7 is a cross-sectional view of the film F shown in the example, and is a diagram schematically showing a chemical reaction in the film F during exposure. FIG. 8 is a cross-sectional view similar to FIG. 7, schematically showing a chemical reaction in the film F during heating. In the film F, a photosensitive layer mainly composed of polyvinyl butyral is formed on a support (base layer) made of PET, and a protective layer made of cellulose butyrate is further formed thereon. The photosensitive layer contains silver behenate (Beh. Ag), a reducing agent and a toning agent.

When the film F is irradiated with the laser beam L from the exposure unit 120 during exposure, as shown in FIG.
Silver halide grains are exposed to the area irradiated with the laser beam L, and a latent image is formed. On the other hand, when the film F is heated to a temperature equal to or higher than the minimum thermal development temperature, as shown in FIG. 8, silver ions (Ag ⁺ ) are released from the silver behenate, and the behenic acid releasing the silver ions is complexed with the toning agent and the complex. To form Thereafter, silver ions are diffused, and the reducing agent acts with the exposed silver halide grains as nuclei to form a silver image by a chemical reaction. As described above, 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 less,
Thermal development is performed at a temperature not lower than the minimum development temperature of not less than ° C.

The light-sensitive silver halide used in the heat-developable material is typically 0.75 to 25 with respect to the organic silver salt.
mol% can be used, preferably
It can be used in the range of 2 to 20 mol%.

The silver halide may be silver bromide, silver iodide, silver chloride, silver bromoiodide, silver chlorobromoiodide,
Any photosensitive silver halide such as silver chlorobromide may be used. The silver halide may be in any form that is photosensitive, including, but not limited to, cubic, orthorhombic, tabular, tetrahedral, and the like.

The organic silver salt is any organic material containing a reduction source of on in silver. Organic acids, especially long chain fatty acids (10
-30 carbon atoms, preferably 15-28 carbon atoms)
Are preferred. When the ligand is 4.0 to 10.0 overall
It is preferable that the organic or inorganic silver salt complex has a certain stability between the two. Then, about 5% of the weight of the image forming layer
It is preferably about 30%.

The organic silver salt which can be used in the heat developing material is a silver salt which is relatively stable to light, and which contains an exposed photocatalyst (for example, silver halide for photography) and a reducing agent. Is a silver salt that forms a silver image when heated to a temperature of 80 ° C. or higher.

Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. They include silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver stearate and the like. Silver salts with halogen atoms or hydroxyl in aliphatic carboxylic acids can also be used effectively. Silver salts of compounds having a mercapto or thione group and derivatives thereof can also be used. Further, a silver salt of a compound having an imino group can be used.

The reducing agent for the organic silver salt may be any material that can reduce silver ions to metallic silver, and is preferably an organic material. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful. However, phenol reducing agents are preferred. The reducing agent is used in the image forming layer.
It should be present at 10% by weight. In a multi-layer configuration,
If the reducing agent is added to a phase other than the emulsion layer, a slightly higher proportion, about 2 to 15% by weight, is more desirable.

[0089]

EXAMPLE When the film F described below was thermally developed by the above-described apparatus according to the present embodiment and the apparatus according to the modification, no unevenness in density or unevenness possibly caused by manufacturing accuracy was found. Hereinafter, the film F will be described.

A silver halide-silver behenate dry soap was prepared by the method described in US Pat. No. 3,839,049. The silver halide had 9 mole% of the total silver, while silver behenate had 91 mole% of the total silver.
The silver halide has 0.055% 2% iodide.
It was a μm silver bromoiodide emulsion.

The heat-developable emulsion was homogenized with 455 g of the above-mentioned silver halide-silver behenate dry soap, 27 g of toluene, 1918 g of 2-butanone, and polyvinyl butyral (B-79 manufactured by Monsanto). The homogenized heat-developed emulsion (698 g) and 60 g of 2-butanone were cooled to 12.8 ° C. while stirring. Pyridinium hydrobromide perbromide (0.92 g) was added and stirred for 2 hours.

3.25 ml of a calcium bromide solution (CaBr (1 g) and 10 ml of methanol) were added, followed by stirring for 30 minutes. Further, polyvinyl butyral (158 g; B-79 manufactured by Monsanto) was added, and 20
Stirred for minutes. The temperature was raised to 21.1 ° C. and the following was added with stirring over 15 minutes.

3.42 g of 2- (tribromomethylsulfone) quinoline, 28.1 g of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane, 5-methylmercapto 41.1 g of a solution containing 0.545 g of benzimidazole, 6.12 g of 2- (4-chlorobenzoyl) benzoic acid 0.14 g of S-1 (sensitizing agent) 34.3 g of methanol Isocyanate (Desmoder N3300, Mobe 2.14 g Tetrachlorophthalic anhydride 0.97 g Phthalazine 2.88 g The dye S-1 has the following structure.

[0094]

Embedded image

An active protective topcoat solution was prepared using the following components: 2-butanone 80.0 g methanol 10.7 g cellulose acetate butyrate (CAB-171-155, Eastman Chemicals) 8.0 g 4-methylphthalate Acid 0.52 g MRA-1, Mottle reducing agent, N-ethyl perfluorooctanesulfonylamide Ethyl methacrylate / hydroxyethyl methacrylate / acrylic acid weight ratio 70:20:10 Tertiary polymer 0.80 g This thermally developed emulsion and topcoat And 0.18 at the same time
mm blue polyester film base. The knife coater was set up with two bars or knives coating simultaneously at a distance of 15.2 cm. The silver trip layer and the top coat were multi-layer coated by pouring the silver emulsion on the film prior to the rear knife and the top coat on the film prior to the front bar.

The film was then pulled forward so that both layers were coated simultaneously. This was obtained by performing the multilayer coating method once. The coated polyester base was dried at 79.4 ° C. for 4 minutes. As the knife, as dry coating weight per 1 m ² for the silver layer is 23g, then dry coating weight per 1 m ² is adjusted so as to be 2.4g for the top coat Was.

[0097]

According to the present invention, it is possible to reduce unevenness and uneven development in a heat-developable material.

[Brief description of the drawings]

FIG. 1 is a front view of a heat developing device according to an embodiment of the present invention.

FIG. 2 is a left side view of the heat developing device according to the embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a configuration of an exposure unit 120.

FIG. 4 is a diagram illustrating a configuration of a developing unit that heats a film, and is a perspective view of the developing unit.

5 is a cross-sectional view of the configuration of FIG. 4 taken along line IV-IV and viewed in the direction of the arrow.

FIG. 6 is a front view of the configuration of FIG. 4;

FIG. 7 is a cross-sectional view of the film F, schematically showing a chemical reaction in the film F during exposure.

FIG. 8 is a cross-sectional view similar to FIG. 7, schematically showing a chemical reaction in the film F during heating.

FIG. 9 is a perspective view showing end portions of a drum 14 and a roller 16;

10 is a view of the drum 14 and the roller 16 of FIG. 9 as viewed in the direction of the arrow X.

FIG. 11A is a diagram showing a first modification. FIG. 11B is a diagram illustrating a second modification.

FIG. 12 is a diagram showing a third modified example.

FIG. 13 is a diagram showing a fourth actual modified example.

FIG. 14 is a diagram showing a fifth modification.

FIG. 15 is a diagram showing a sixth modification.

[Explanation of symbols]

 14 Drum 16 Roller 18 Frame 21 Guide bracket 28 Coil spring 30 Reinforcement member 32 Heater 34 Electronic device 38 Surface layer 100 Thermal development device 110 Storage unit 120 Exposure unit 130 Development unit 143 Transport roller 150A Cooling unit 150 Control device 151 Motor 203 Cooling roller F film M Roller drive motor

Claims (5)

[Claims] A heating member that heats the photothermographic material while transporting the photothermographic material while holding the photothermographic material on a holding surface; and a rotatable guide that urges and guides the photosensitive material held by the heating member against the heating member. A heat developing device for thermally developing the photosensitive material, comprising: a driving member; a driving force transmitting mechanism for transmitting a driving force of the driving source to the guiding member to rotate the guiding member; The surface layer of the heating member has a hardness of 30 to 80 ° and a thickness of 0.1 mm.
A heat developing device comprising an elastic body of 3 to 2 mm. 2. A heating member for heating the photothermographic material while transporting it while holding the photothermographic material on a holding surface, and a rotatable member for urging and guiding the photosensitive material held by the heating member to the heating member. A heat developing device for thermally developing the photosensitive material, wherein a member for increasing the rotational moment of inertia of the guide member is provided on the guide member, and the surface layer of the heating member has a hardness of 3
A heat developing apparatus, which is an elastic body having a thickness of 0 to 80 ° and a thickness of 0.3 to 2 mm. 3. A heating member for heating the photothermographic material while transporting it while holding the photothermographic material on a holding surface, and a rotatable member for urging and guiding the photosensitive material held by the heating member to the heating member. A heat developing device for thermally developing the photosensitive material, comprising: a rotary inertia member having a rotational inertia moment larger than a rotational inertia moment of the guide member interlocked with the guide member; The surface layer has a hardness of 30 to 80 ° and a thickness of 0.
A heat developing device comprising an elastic body of 3 to 2 mm. 4. The heat developing apparatus according to claim 1, wherein the elastic body has a surface roughness of 1.6 μm or less. 5. The heat developing apparatus according to claim 1, wherein said guide member is made of a metal material.