JP2000258888A - Heat developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat developing device capable of suppressing the occurrence of density unevenness and stabilizing the density by once lowering the temperature of a heating member before heat development of the next heat developing material after heat development of a previous heat developing material, then heating the heat developing material to the prescribed heat development temperature. SOLUTION: A film is stripped from the outer peripheral surface of a drum 14 by a guide plate 202a after the outer peripheral surface temperature in the central part of the drum 14 is once lowered. The stripped film is sent from a discharge port 202 of the film to a cooling section 150A. A drive assembly moves a movable frame 203a inward in a radial direction in such a manner that a cooling roller 203 comes into contact with the outer peripheral surface of the drum 14. As a result, the temperature of the outer peripheral surface of the drum 14 falls at a time. When the temperature falls, the drive assembly retreats the cooling roller 103 from the outer peripheral surface of the drum 14 to prevent the useless temperature fall. The outer peripheral temperature of the drum 14 is thereafter elevated by heating with a heater 32 and is made uniform in the longitudinal direction of the drum 14.

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, and more particularly to a heat developing apparatus for forming an image by holding a heat developing material on a heated outer peripheral surface of a drum.

[0002]

2. Description of the Related Art By continuously supplying a sheet-like heat developing material to an outer peripheral surface of a heated drum, a thermal reaction occurs in the heat developing material, whereby an image formed as a latent image can be visualized. A heat developing device capable of forming a target image has been developed (see Japanese Patent Application Laid-Open No. 10-500977).
According to such a thermal developing device, a sheet-like thermal developing material is
It is supplied to the outer peripheral surface of the drum rotating at a constant rotation speed, and after the drum rotates by a predetermined rotation angle while holding the thermal developing material, the heated thermal developing material is peeled off from the outer peripheral surface of the drum, and at the same time, a new one is obtained. Since the thermal developing material is supplied to the outer peripheral surface of the drum, it is possible to efficiently heat the sheet-like thermal developing material.

[0003]

By the way, a heat developing device (for example, Japanese Patent Application Laid-Open No. 10-101) which heats a heat developing material while holding it by a heating member whose temperature is controlled to a predetermined heat developing temperature.
In the apparatus disclosed in Japanese Patent No. 500497, it has been found that when another heat development material is heat-developed immediately after heat development of the heat development material, density unevenness may occur in the latter heat development material.

An object of the present invention is to provide a heat developing apparatus and a heat developing method capable of suppressing the occurrence of such density unevenness and stabilizing the density.

[0005]

Means and Means for Solving the Problems The present inventors have made intensive studies on the causes of the occurrence of such density unevenness, and as a result, have found the following and have made the present invention.

In other words, immediately after the heat development of the heat development material, the heat is taken away in the area where the previous heat development material is held, and the heat is not taken away so much in the other areas. In this case, a temperature difference occurs between the region where the heat development has been performed and the other region, and this may cause density unevenness in the thermally developed material that has been thermally developed next. Then, if the temperature control for maintaining the predetermined thermal development temperature is continued,
This temperature difference is not easily resolved.

Therefore, a heat developing apparatus according to one aspect of the present invention uses the heating member in a state where the heat development material is substantially adhered to the surface of the heating member whose temperature is controlled to a predetermined heat development temperature. In a thermal developing apparatus that heats and develops a heat developing material, when a plurality of thermal developing materials are successively thermally developed, if at least a predetermined condition is satisfied, the next heat developing material is thermally developed, and Before thermally developing the thermally developed material, the temperature of the heating member is once lowered and then heated to a predetermined thermal development temperature. Thus, by once lowering the temperature of the heating member and then heating it to a predetermined heat development temperature, the temperature difference between the area holding the heat development material and the other area can be quickly and substantially eliminated. ,
The occurrence of density unevenness is suppressed.

Further, the heat developing apparatus according to one aspect of the present invention is characterized in that the heat developing material is substantially adhered to the surface of the heating member whose temperature is controlled to a predetermined heat developing temperature by the heating member. In a thermal developing apparatus that heats and develops a heat developing material, when a plurality of thermal developing materials are successively thermally developed, if at least a predetermined condition is satisfied, the next heat developing material is thermally developed, and A heat developing apparatus comprising: a cooling unit that cools a region not holding the heat developing material in the previous heat development before the heat developing material is thermally developed. Thereby, the area not holding the heat developing material is cooled, and the temperature difference between the area holding the heat developing material and the other area can be substantially eliminated, thereby suppressing the occurrence of density unevenness. . Examples of such a cooling means include, but are not limited to, a Peltier element, an electronic cooling element, a heat pipe, and a cooled high thermal conductor.

When a plurality of thermal development materials are successively thermally developed, if at least a predetermined condition is satisfied, the thermal development of the previous thermal development material is performed before the thermal development of the next thermal development material. By bringing at least the region of the heating member that holds the thermal development material in the next thermal development into close contact with the high thermal conductor, even if the temperature unevenness due to cooling occurs on the surface of the heating member, the high thermal conductive member allows The heat is efficiently and quickly transmitted from the heat source to the low-temperature portion, and the temperature unevenness can be eliminated more quickly. In particular, after lowering the temperature of the heating member, by bringing at least the region for holding the heat development material in the next heat development of the heating member into close contact with the high thermal conductor, the temperature unevenness caused by cooling is also excellent. And the occurrence of density unevenness can be further suppressed.

According to one aspect of the present invention, there is provided a heat developing apparatus, wherein a heat developing material is substantially adhered to a surface of a heating member which is temperature-controlled at a predetermined heat developing temperature. In a thermal developing apparatus that heats and develops a material, when a plurality of thermal developing materials are successively thermally developed, if at least a predetermined condition is satisfied, the next thermal developing material is thermally developed after the previous thermal developing material is developed. A heat developing apparatus, wherein at least a region of the heating member for holding the heat development material in the next heat development is brought into close contact with a high heat conductor before heat development of the development material. Thereby, heat is efficiently and quickly transmitted from the high-temperature portion to the low-temperature portion by the high heat conductive member, so that temperature unevenness can be suppressed, and occurrence of density unevenness can be suppressed.

The heating member is a rotating body, and has a supply section for supplying the heat development material to the heating member, and a discharge section for discharging the heat development material from the heating member. In addition, it is possible to automatically and continuously develop the heat-developable material while suppressing the occurrence of density unevenness due to the continuous heat development. In particular, since it is possible to develop a plurality of sizes of the heat developing materials having different lengths in the rotation axis direction of the heating member, it is not necessary to prepare a heat developing device for each of the different sizes of the heat developing materials. Although the thermal development material can be thermally developed, it is easily affected by temperature unevenness in the rotation axis direction of the heating member. However, with the above-described means, it is possible to favorably suppress the occurrence of temperature unevenness and the occurrence of density unevenness.

It is preferable that the heating member heats the heat development material at a development temperature not lower than the minimum development temperature for a heat development time.

[0013] Further, by having a rotatable roller urged against the heating member, the heat development material is pressed against the heating member by the roller and closely adhered thereto, so that uneven heating of the heat development material can be suppressed. The occurrence of density unevenness can be more effectively suppressed.

Further, a thickness of 0.1 m is provided on the surface of the heating member.
By providing the elastic layer having a thickness of m or more, the heat-developable material adheres more closely to the surface of the drum, so that uneven heating of the heat-developable material can be suppressed, and the occurrence of density unevenness can be suppressed more effectively.

In particular, when the elastic layer has a thickness of 2 mm or less,
The heat conductivity is 0.4 W / mk or more, and the heating member has a metal supporting member that directly or indirectly supports the elastic layer, so that heat from the heating member is transferred to the heat developing material. It is possible to transmit sufficiently, and it is possible to suppress the occurrence of temperature unevenness inside the heating member while obtaining a sufficient thermal development speed, to further suppress the occurrence of temperature unevenness, and to suppress the occurrence of density unevenness.

The heat-developable material contains photosensitive silver halide grains, an organic silver salt, and a silver ion reducing agent,
Thermal development is not substantially performed at a temperature of 40 ° C. or less, and thermal development is performed at a temperature of a minimum development temperature of 80 ° C. or more, so that thermal development can be performed with sufficient productivity. Easy to receive. However, by the means described above,
The occurrence of temperature unevenness is sufficiently suppressed, and the occurrence of density unevenness is suppressed.

[0017]

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. FIG. 1 is a front view of a heat developing apparatus according to an embodiment of the present invention, and FIG.
FIG. 2 is a left side view of the heat developing device. Thermal developing device 1
Reference numeral 00 denotes a feeding unit 110 that feeds the film F, which is a sheet-like heat developing material shown in Example, one by one, an exposure unit 120 that exposes the fed film F, and And a developing unit 130 for developing. Figure 1
2, the operation of the thermal developing apparatus 100 will be described.

In FIG. 2, feeding units 110 are provided in two stages, upper and lower, and a film F (FIG. 3, FIG.
4) is stored for each case C. The feeding unit 110
The film F is taken out of the case C by a take-out device (not shown) and pulled out in the direction (horizontal direction) shown by the arrow (1) in the figure. Further, a transport device 141 including a roller pair
The film F pulled out of the case C is transported in a direction (downward) indicated by an arrow (2) in the figure.

The film F conveyed below the heat developing device 100 is further conveyed to a conveying direction changing unit 145 below the heat developing device 100, and the conveying direction changing unit 145 changes the conveying direction of the film F. (Arrow (3) in FIG. 2 and arrow (4) in FIG. 1), the process proceeds to the exposure preparation stage. Further, the transport device 142 composed of a pair of rollers transports the film F from the left side surface of the thermal developing device 100 in the direction (upward) indicated by the arrow (5) in FIG. The film F is irradiated with a laser beam L in an infrared range of 780 to 860 nm, for example, a laser beam of 810 nm.

Upon receiving the laser beam L, the film F forms a latent image in a manner described later. Thereafter, the supply roller pair 143 conveys the film F in the direction (upward) indicated by the arrow (6) in FIG. That is, they are supplied at random timing.

The supply roller pair 143 is connected to the drum 14
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. 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 rotates together in the direction shown by the arrow (7) in FIG. 1 with the film F and the outer periphery of the drum 14 in close contact with each other. In this state, the drum 14 heats and thermally develops the film F. That is, the latent image of the film F is formed as a visible image. Thereafter, when the film F rotates to the right with respect to the drum 14 in FIG. 1, the film F is separated from the drum 14 and cooled while being transported in the direction indicated by the arrow (8) in FIG. After that, the transport device 144
The film F separated from the drum 14 is transported in the directions shown by arrows (9) and (10) in FIG. 1 and is discharged to a discharge tray 160 so that the film F can be taken out from the upper portion of the thermal developing device 100.

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

A more specific configuration will be described below. In FIG. 3, an image signal S which is a digital signal output from an image signal output device 121 is converted into an analog signal by a D / A converter 122 and input to a modulation circuit 123. The modulation circuit 123, based on the analog signal,
The driver 124 of the laser light source unit 110 is controlled to emit the modulated laser light L from the laser light source unit 110.

The laser light L emitted from the laser light source unit 110 is converged only in the vertical direction by the cylindrical lens 115, and is applied to the rotating polygon mirror 113 rotating in the direction of arrow A in FIG. The light is incident as an image. The rotary polygon mirror 113 reflects and deflects the laser light L in the main scanning direction.
After passing through an fθ lens 114 including a cylindrical lens formed by combining two lenses, the light is reflected by a mirror 116 provided on the optical path so as to extend in the main scanning direction, and is conveyed in a direction indicated by an arrow Y by a conveying device 142. The main scanning is repeatedly performed in the direction of the arrow X on the surface to be scanned of the film F (sub-scanned). That is, the laser beam L scans over 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.
It converges only in the sub-scanning direction.
The distance from the θ lens 114 to the surface to be scanned of the film F is equal to the focal length of the fθ lens 114 as a whole. Thus, in the main exposure unit 120, f including the cylindrical lens 115 and the cylindrical lens
Since the θ lens 114 is provided so that the laser beam L is once converged only in the sub-scanning direction on the rotating polygon mirror 113, even if the rotating polygon mirror 113 is tilted or shakes, On the surface to be scanned of the film F, the scanning position of the laser beam L does not shift in the sub-scanning direction, so that scanning lines of equal pitch 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 developing section 130 for heating the film F. More specifically, FIG.
5 is a perspective view of the developing unit 130 as viewed obliquely from the rear, FIG. 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, and FIG. It is the figure which looked at the composition from the side.

The developing section 130 has a drum 14 which can heat the film F while holding it on the outer periphery. Drum 14
The film F at a temperature equal to or higher than a predetermined minimum heat development temperature
The film F is thermally developed by maintaining a predetermined thermal 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, it is preferable that the film F is not substantially thermally developed at 40 ° C. or lower, which is the environmental temperature at which the apparatus can be installed.

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

Outside the drum 14, there are provided 27 small-diameter rollers 16 as guide members, which are arranged parallel to the drum 14 and at equal intervals in the circumferential direction of the drum 14. 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 the gap 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. develop.

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 (not shown) is formed on a rotating shaft 23 of a micro step motor (not shown) which is arranged 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 micro-step motor is transmitted to the shaft 22 via a timing belt (belt with a gear) 25 connecting the two gears, whereby the drum 14 rotates. In addition, from the rotation shaft 23 to the shaft 22
The transmission of power to the motor may be performed via a chain or a gear train instead of the timing belt.

As shown in FIG. 5, in the present embodiment, the roller 16 is approximately 234 around the drum 14 in the circumferential direction.
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 control electronic device 34 shown in FIG. Power is supplied to the heater 32 through 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 device 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 an aluminum support tube 36, which is a metal support member, and a flexible layer (elastic layer) 38 attached to the outside of the support tube 36. ing. The flexible 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 flexible layer 38 has a sufficiently smooth surface to increase the degree of adhesion to the film F to be heated.
The surface roughness Ra is desirably smaller than 5 μm (particularly 2 μm).

However, in order to prevent the film F from sticking to the drum 14, the surface roughness Ra of a specific material such as a silicon rubber-based material is
It is better to 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 flexible layer 38 and the film F.

The flexible 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 flexible layer 38 is 0.4 W / m /
K or more.

Since the flexible layer 38 is used, the roller 16 ensures that the film F comes into close contact with the drum 14 without sacrificing wear resistance. The flexible layer 38 has a Shore A measured with a durometer.
The hardness is preferably 70 or less (especially 60 or less). In the present embodiment, the Shore A hardness measured by a durometer is 55 or less.

In this embodiment, an additive for increasing the thermal conductivity and silicon rubber are contained, and such a material is particularly useful for forming the flexible layer 38. Have been found. Although the thermal conductivity of the silicone rubber contained in such a material is relatively small, the silicone rubber has a pressing performance of the film F,
The durability (abrasion resistance) with respect to the film F is improved.

On the other hand, in order to improve the processing capacity of development, it is necessary to increase the thermal conductivity. However, the above-mentioned additives in the material contribute to maintaining the thermal conductivity at a high level. It is. However, in the material forming the flexible layer 38, if the amount of the additive is increased, the pressing performance and durability of the silicone rubber are reduced.
It is necessary to balance the amounts of the additives and the silicone rubber within a certain range. The silicon rubber-containing material has an advantage that it is easily separated from the film F and is chemically inert.

The thickness of the flexible layer 38 is from 0.1 mm to 2 m
m, it is possible to use a thinner flexible layer 38. However, as the thickness becomes thinner, the function of the flexible layer 30 deteriorates, and there is a problem that its manufacture becomes difficult. Therefore, the thickness of the flexible layer 38 is
It is preferably 0.3 mm or more. Further, the variation in the thickness of the flexible 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, a rotatable roller 16 is used as a guide member. However, other means, such as a small movable belt, can be used. 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.

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 smaller than 14 g,
There is a possibility that the roller 16 does not wrap around the drum 14. In particular, if the biasing force is 7 g or less, no rotation occurs. In such a case, the film F is
And the roller 16 is in contact with the film F, the film F may be damaged by the roller 16. Therefore, in such a case, it is preferable to provide a rotation driven portion that receives a rotation driving force at both ends of the roller 16 and to rotate the roller 16 by a gear drive, a friction drive, or the like via the rotation drive portion.

On the other hand, the urging force of the coil spring 28 needs to be small enough that the roller 16 does not cause any indentation on the film F. For this reason, the urging force from the roller 16 per 1 cm width of the film F is 200 g or less (in particular, 1 g).
00 g or less). In the present embodiment, the urging force from the roller 16 per 1 cm width of the film F is between 5 and 7 g. In addition, a rotationally driven portion (not shown) is provided at both ends of the roller, and the roller is rotationally driven by a gear drive through the rotationally driven portion, and the force is maintained within this range, thereby reducing indentation. Harmony with reduction of image non-uniformity can be ensured.

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.

The space between the adjacent rollers 16 in addition to the force exerted by each roller 16 can be said to be important in order to form a high quality image on the film F. When the film F is supplied to the drum 14,
The temperature is generally room temperature (approximately 20 ° C.). Therefore, in order to maximize the processing capacity of the developing unit 130,
The film F must be quickly heated from room temperature to the minimum heat development temperature (124 ° C. in the present embodiment) required to start development.

However, the base material contained in a certain type of film F, for example, a plate material based on a polyester film or a plate material based on another thermoplastic (material) is not heat-resistant. It may expand or contract (shrink). Therefore, in order to make the dimensional change uniform so that wrinkles (folds) are not formed, the film F
Must be evenly heated when alternating between a state held flat and an unrestrained state. In order to realize this, the plurality of rollers 16 change the area (region) of the film F located between the adjacent rollers 16 when the film F is not restrained between the rollers 16 and the drum 14. Are provided at intervals so as to allow for

However, as described above, in order to conduct heat sufficiently and uniformly to uniformly develop the film F, the roller 16 is held for a predetermined time while the film F is urged against the drum 14. Must.
As a result, the spacing located between adjacent rollers 16 should be selected so that wrinkles are minimized and that the heating of film F occurs quickly and uniformly. is there.

Further, on the outer periphery of the cylindrical drum 14,
The rigidity of the film F itself causes its leading edge to extend tangentially between the rollers 16, but the rollers 16 must be sufficiently close together to suppress this. Such an arrangement is important for holding the film F between the roller 16 and the drum 14. To do so, it is preferable that the diameter of the drum 14 be 5 cm to 30 cm and the diameter of the roller 16 be 0.5 to 2 cm. This is especially true when the thickness of the base is 0.
Useful for thermally developing 1-0.2 mm films.

As shown in FIGS. 4 to 6, 27 rollers 1
6 are provided over 234 degrees in the direction of rotation of the drum 14, and each space is separated from the center by 9 degrees from the center. This configuration is such that when the diameter of the drum 14 is 16 cm and the diameter of the roller 16 is 1.2 cm, a film having a base thickness of 0.1 to 0.2 mm, for example, a base thickness of It is effective for relatively hard films such as polyester films having a thickness of 0.18 mm, and films having a smaller hardness such as polyester films having a base thickness of 0.10 mm. ing. The heater 32 is attached to 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 heater control electronic device 34 includes the drum 1
4 together with the heater 3 according to the sensed temperature information.
2 can be adjusted. The outer surface temperature of the drum 14 can be adjusted by the heater 32 and the control electronic device 34 so that the temperature becomes suitable for the development of the specific film F. In the present embodiment, the drum 14 can be heated to a temperature of 60C to 160C by the heater 32 and the control electronic device 34.

Here, the heater 32 and the control electronic device 34
Accordingly, it is preferable to maintain the temperature in the width direction of the drum 14 within 2.0 ° C. (particularly, within 1.0 ° C.). In the present embodiment, the temperature is maintained within 0.5 ° C.

The undeveloped film F supplied at a predetermined timing from the supply roller pair 143 is supplied to the nip 52 formed by the heating member 14 and the roller 16 on the most upstream side in the developing section 130. . 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 can move at substantially the same speed as the film F to be developed, the possibility that the surface of the film F is scratched (scratched or damaged) is reduced, thereby ensuring a high quality image. can do. After being transported between the drum 14 and the roller 16, the developed film F is guided by a nip 50 formed by the roller 16 and the drum 14 located at the most downstream side, and
Derived from zero. The developing unit 130 can be configured to develop various films F such as a 0.178 mm polyester base layer coated with a photosensitive heat-developable emulsion containing infrared-sensitive silver halide as described in Examples. . The drum 14 is maintained at a temperature of 115 ° C. to 138 ° C., for example, 124 ° C.
The film F is rotated at a rotational speed such that the film F is kept in contact with the outer peripheral surface for a predetermined time of about 15 seconds. At the predetermined time and the temperature, the film F
It can be raised to a temperature of 4 ° C.

The surface of the film F on the side having the photosensitive heat-developable emulsion layer is preferably in contact with the outer peripheral surface of the drum 14 (the flexible layer 38 in this embodiment).

Subsequent to the thermal development of the image, the film F is guided away from the surface of the drum 14 of the developing unit 130, in a direction separated therefrom, and then guided to the cooling device 150A. 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 a cooling device until the temperature of the film F decreases to a temperature lower than the glass transition temperature of the support of the film F, and thereafter, the temperature is lower than the glass transition temperature of the support of the film F. When the temperature of the film F decreases to
Cools rapidly.

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. Meanwhile, the film F is heated,
When the temperature becomes equal to or higher than the minimum developing temperature, as shown in FIG.
Silver ions (Ag ⁺ ) are released from the silver behenate, and the behenic acid releasing the silver ions forms a complex with the toning agent. 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 the photosensitive silver halide grains, the organic silver salt, and the 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 0 ° C. or higher.

If the sheet-like heat developing material (film F) is not heated uniformly, the temperature of the heat developing material may vary, and the density of the formed image may vary. Therefore, the outer peripheral surface of the drum 14
It is desirable to heat the entire circumference to a uniform temperature of, for example, about 124 ° C.

On the other hand, films of different sizes (for example, A3 and A4 sizes) in the longitudinal (width) direction of the drum are
It is convenient if development can be performed by the same thermal developing device. However,
If a large-sized film is heated after a small-sized film is heated, the following problem occurs.

The film F stored at room temperature was placed on the drum 1
When supplied to the outer peripheral surface of the drum 4, the temperature of the outer peripheral surface of the drum 14 decreases in a region in contact with the film F. Here, when a film F of a large size that is substantially equal to the length in the longitudinal direction of the drum 14 is supplied, the entire outer peripheral surface of the drum 14 is cooled. Irrespective of this, no temperature variation occurs in the width direction.

However, when a film F having a short length in the longitudinal direction (rotational axis direction) of the drum 14 is supplied to the drum 14, the following problems occur. FIG. 9 is a diagram showing the temperature of the outer peripheral surface of the drum 14 on the vertical axis and the length of the drum 14 in the longitudinal direction on the horizontal axis. The longitudinal length of the effective heating area of the drum 14 is 2B.

In FIG. 9, assuming that a short width B film is supplied to the center of the drum 14, the surface temperature decreases by ΔT over the width B. In such a case, a large size (width 2)
When the film (B) is supplied next, a temperature variation of a low center and high sides occurs in the same film heated by the drum 14, which may cause a density variation of an image. With respect to such a problem, according to the present embodiment, it is possible to eliminate unevenness in the outer peripheral surface temperature of the drum 14 and thereby to prevent temperature variation of the film. A first example of such a thermal developing device will be described below.

In FIG. 5, a film supply port 201 is provided.
And a film discharge port 202, four cooling rollers 203 are rotatably supported by a movable frame 203a. The cooling roller 203 is connected to the drum 14
Having a length substantially equal to the length in the longitudinal direction of 10 W / m /
It is formed of a material having high thermal conductivity of K or more. The movable frame 203a is movable in the radial direction with respect to the drum 14 by a driving device (not shown). When the movable frame 203 moves inward in the radial direction, the cooling roller 203 comes into contact with the outer peripheral surface of the drum 14.
03 is separated from the outer peripheral surface of the drum 14. The thermal conductivity of the cooling roller is preferably at least 20 W / m / K (particularly at least 50 W / m / K). Examples of such a material having high thermal conductivity include aluminum, copper, and brass, but are not limited thereto.

Next, the operation of the first example will be described. In FIG. 5, first, a film F having a width B, which is a small size, is supplied from a film supply port 201 through a guide plate 20.
1a, and is supplied to the outer peripheral surface of the drum 14. As shown in FIG. 9, after the temperature of the outer peripheral surface of the central portion of the drum 14 is reduced, the film F
02a, it is peeled off from the outer peripheral surface of the drum 14,
The film is sent from the film outlet 202 to the cooling unit 150A.

Incidentally, a driving device (not shown) can determine the size of the film F based on a signal from the cassette C (FIG. 1) from which the film F has been taken out. Therefore, when the drive device determines that the film F of a small size has been supplied, the driving roller 20
The movable frame 203a is moved inward in the radial direction so that 3 contacts.

With this operation, the temperature of the outer peripheral surface of the drum 14 decreases from the solid line T1 to the dotted line T2 in FIG. When the temperature drops to the dotted line T2, the driving device retracts the cooling roller 203 from the outer peripheral surface of the drum 14 to prevent unnecessary temperature drop. Thereafter, by the heating of the heater 32, the outer peripheral surface temperature of the drum 14 rises to the two-dot chain line in FIG. 9 and becomes uniform in the longitudinal direction of the drum 14. It takes two to three minutes for the outer peripheral surface temperature of the drum 14 to decrease from the solid line T1 in FIG. 9 to the two-dot chain line T3 by natural cooling, but according to the present embodiment, the outer peripheral surface of the drum 14 is Since the surface temperature is decreased from the solid line T1 in FIG. 9 to the dotted line T2 and then increased to the two-dot chain line T3, a short time as short as 30 seconds is sufficient, thereby shortening the lead time for supplying the next film F. Thus, image formation can be performed efficiently. In order to prevent temperature unevenness, it is desirable to reduce the wind that hits the surface of the drum 14 as much as possible.

FIG. 10 is a perspective view showing a second example.
The second example is different from the first example described above in that the pair of rollers 213 does not contact the small-sized film F on the outer peripheral surfaces at both ends of the drum 14 and does not contact the small contact area C. This is a point that is arranged so as to be able to contact the. According to this embodiment, the drive device (not shown) brings the cooling roller 213 into contact with the area C of the drum 14 when determining that the film F having a small size (width B) has been supplied. Thereby, only the temperature in the region C of the drum 14 directly decreases from the solid line T1 in FIG. 9 to the two-dot chain line T3. When the temperature drops to the dotted line T2, the driving device retracts the roller 213 from the area C of the drum 14 to prevent unnecessary temperature drop. On the other hand, if the drive device determines that the film F of a large size (width 2B) has been supplied, the driving device maintains the state in which the cooling roller 213 is retracted from the outer peripheral surface of the drum 14, thereby reducing the temperature of the outer peripheral surface of the drum 14. It can be uniform.

In order to improve the cooling efficiency of the cooling roller 213, the cooling roller 213 may be hollow, and the cooled fluid LC may be appropriately fed through the supply pipe 213a. Further, if the warmed fluid LC is sent to the cooling roller 213, it can be used as a heater for partially increasing the outer peripheral surface temperature of the drum 14.

FIG. 11 is a view similar to FIG. 5, showing a third example. 11, a cooling belt device 223 is provided instead of the cooling roller 203. The cooling belt device 223 has a belt 223 a having high thermal conductivity that contacts the outer peripheral surface of the drum 14. Belt 223a
Since the contact area with the outer peripheral surface of the drum 14 is larger than that of the roller 203, the drum 4 can be cooled more efficiently. Note that other configurations and operations are the same as those in the above-described first or second example, and thus description thereof will be omitted.

A fourth example will be described with reference to FIG. 9 (where 203 is a fixed frame in the fourth example). The fixed type frame 203 rotatably holds the plurality of solid high heat conductive rollers 203 so as to urge the outer peripheral surface of the drum 14 (the flexible layer 38 in this embodiment). The thermal conductivity of the high thermal conductive roller 203 is 20
It is preferably at least W / m / K (particularly at least 50 W / m / K). Materials with such high thermal conductivity include:
Examples include, but are not limited to, aluminum, copper, brass, and the like. Thereby, the temperature unevenness of the outer peripheral surface (the flexible layer 38 in the present embodiment) of the drum 14 can be made uniform to such an extent that it does not substantially cause a problem. High heat conduction roller 2
No. 03, the urging force per 1 cm of the width of the high thermal conductive roller to the drum 14 is 7 g or more (especially 14 g or more (further 30 g).
Above), the high thermal conductive roller 203
4 is preferable because it suppresses temperature unevenness on the outer peripheral surface of the drum 14 and suppresses scratching. The heat of the flexible layer 38 of the drum 14 is preferably 300 g or less (particularly 100 g or less). It is preferable for suppressing creep phenomenon and plastic deformation due to pressure. In the example experiment, 30
４０40 g.

The photosensitive silver halide used in the heat-developable material is typically from 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 is 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.

Organic silver salts are all organic materials that contain a source of silver on reduction. 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 is composed of an exposed photocatalyst (for example, silver halide for photography) and the presence of 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 capable of reducing 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.

Binders suitable for the photothermographic material of the present invention are transparent or translucent, generally colorless, and include natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as: gelatin, gum arabic, (Vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid) , Copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinylacetal) s, poly (ester)
, Poly (urethane) s, phenoxy resins, poly (vinylidene chloride), poly (epoxides), poly (carbonates), poly (vinyl acetate), cellulose esters, and poly (amides). Although it may be hydrophilic or hydrophobic, in the present invention, it is preferable to use a hydrophobic transparent binder in order to reduce fog after thermal development. Preferred binders include poly (vinyl butyral), cellulose acetate, cellulose acetate butyrate, polyester, polycarbonate,
Examples include polyacrylic acid and polyurethane. Among them, polyvinyl butyral, cellulose acetate,
Cellulose acetate butyrate and polyester are particularly preferably used.

Further, in order to protect the surface of the photosensitive material and prevent abrasion, a non-photosensitive layer may be provided outside the photosensitive layer. The binder used for these non-photosensitive layers may be the same as or different from the binder used for the photosensitive layers.

In the present invention, the amount of the binder in the photosensitive layer is preferably 1.5 to 10 g / m ² in order to increase the speed of thermal development. More preferably, 1.7 to 8 g / m
² If it is less than 1.5 g / m ² , the density of the unexposed portion will increase significantly and may not be usable.

In the present invention, a matting agent is preferably contained on the photosensitive layer side, and in order to prevent damage to the image after thermal development, it is preferable to provide a matting agent on the surface of the photosensitive material. It is preferable that the matting agent is contained in a weight ratio of 0.5 to 30% with respect to all binders on the photosensitive layer side.
In the case where a non-photosensitive layer is provided on the surface opposite to the photosensitive layer with the support interposed therebetween, it is preferable that at least one layer on the non-photosensitive layer side contains a matting agent, and that the light-sensitive material has slipperiness and fingerprint adhesion. For prevention, it is preferable to provide a matting agent on the surface of the photosensitive material, and the matting agent is contained in a weight ratio of 0.5 to 40% with respect to all binders in the layer on the side opposite to the photosensitive layer side. preferable.

The material of the matting agent used in the present invention may be either an organic substance or an inorganic substance. For example, as the inorganic substance, silica, glass powder, alkaline earth metal or a carbonate such as cadmium, zinc or the like can be used as a matting agent. Organic substances include starch, starch derivatives,
Organic matting agents such as polyvinyl alcohol, polystyrene or polymethacrylate, polyacrylonitrile, and polycarbonate can be used.

The shape of the matting agent may be either regular or irregular, but is preferably regular and spherical. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. In the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere.

The matting agent used in the present invention preferably has an average particle size of 0.5 μm to 10 μm, more preferably 1.0 μm to 8.0 μm. The matting agent has a coefficient of variation of the particle size distribution of preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the variation coefficient of the particle size distribution is a value represented by the following equation.

(Standard deviation of particle size) / (average value of particle size) × 100 The matting agent according to the present invention can be contained in any constituent layer, but is preferably used in order to achieve the object of the present invention. Is a constituent layer other than the photosensitive layer, and is more preferably the outermost layer as viewed from the support.

The method of adding the matting agent according to the present invention may be a method of dispersing in a coating solution in advance and applying the solution.
A method of spraying a matting agent after the application liquid is applied and before the drying is completed may be used. When a plurality of types of matting agents are added, both methods may be used in combination.

The photothermographic material of the present invention has at least one photosensitive layer on a support. Although only the photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer on the photosensitive layer. In order to control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer on the same side as the photosensitive layer and / or an antihalation dye layer on the opposite side, a so-called backing layer may be formed,
The photosensitive layer may contain a dye or a pigment. As the dye to be used, any compound may be used as long as it has a desired absorption in a desired wavelength range.

The non-photosensitive layer preferably contains the binder or matting agent described above, and may further contain a slip agent such as a polysiloxane compound, wax or liquid paraffin.

The photosensitive layer may be a plurality of layers, or the photosensitive layer may be a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / high-sensitivity layer for adjusting the gradation.

The photothermographic material of the present invention is for forming a photographic image by a heat development process, and comprises a reducible silver source (organic silver salt), a photosensitive silver halide, a reducing agent and, if necessary, silver. It is preferable that the photothermographic material contains a color toning agent which suppresses the color tone of the present invention in a state of being usually dispersed in an (organic) binder matrix. The photothermographic material of the present invention is stable at room temperature, but is exposed to a high temperature (for example, 80 ° C to 14 ° C).
(0 ° C.). Heating generates silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. The silver formed by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image. This reaction process proceeds without supplying a processing liquid such as water from the outside.

Examples of suitable toning agents used in the present invention are R
D17029 discloses the following. Imides (eg, phthalimide); cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-
Thiazolidinedione); naphthalimides (for example,
N-hydroxy-1,8-naphthalimide); cobalt complex (for example, hexamine trifluoroacetate of cobalt); mercaptans (for example, 3-mercapto-1,2,4-triazole); N- (aminomethyl)
Aryldicarboximides (eg, N- (dimethylaminomethyl) phthalimide); blocked pyrazoles, isothiuronium
um) derivatives and certain photobleaches (eg, N, N'-hexamethylene (1-carbamoyl-
3,5-dimethylpyrazole), 1,8- (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate), and 2- (tribromomethylsulfonyl) benzothiazole combinations); merocyanine dyes (e.g., , 3-ethyl-5-((3-ethyl-2-benzothiazolinylidene (benzothiazolinylidene))-
1-methylethylidene) -2-thio-2,4-oxazolidinedione); phthalazinone, a phthalazinone derivative or a metal salt of these derivatives (for example, 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7 −
Dimethyloxyphthalazinone and 2,3-dihydro-
1,4-phthalazinedione); a combination of phthalazinone and a sulfinic acid derivative (eg, 6-chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); a combination of phthalazine + phthalic acid Phthalazine (including adducts of phthalazine) and maleic anhydride, and phthalic acid, 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivatives and anhydrides thereof (eg, phthalic acid, 4-methylphthalic acid, 4- A combination with at least one compound selected from nitrophthalic acid and tetrachlorophthalic anhydride; quinazolinediones, benzoxazine, naloxazine derivatives; benzoxazine-2,4
-Diones (for example, 1,3-benzoxazine-2,
4-dione); pyrimidines and asymmetric-triazines (e.g., 2,4-dihydroxypyrimidine), and tetraazapentalene derivatives (e.g., 3,6-dimercapto-1,4-diphenyl-1H, 4H-2) , 3a,
5,6a-tetraazapentalene). Among these, phthalazone or phthalazine is preferred as a toning agent.

In the present invention, a mercapto compound, a disulfide compound, and a thione compound are contained in order to suppress or accelerate development to control development, to improve spectral sensitization efficiency, to improve storage stability before and after development, and the like. be able to.

When a mercapto compound is used in the present invention, it may be of any structure,
Those represented by -SS-Ar are preferred.

In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or a condensed aromatic ring having at least one nitrogen, sulfur, oxygen, selenium or tellurium atom. Preferably, the heteroaromatic ring is benzimidazole, naphthymidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole,
Benzoselenazole, benzotellazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogens (eg, Br and Cl), hydroxy, amino,
Carboxy, alkyl (eg, one or more carbon atoms,
Preferably those having 1 to 4 carbon atoms and alkoxy (e.g. one or more carbon atoms, preferably 1 to 4 carbon atoms).
Which have four carbon atoms). Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzothiazole, 3-mercapto-1,2,4-triazole, -Mercaptoquinoline, 8-mercaptopurine, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-hydroxy-2-mercaptopyrimidine,
-Mercapto-4-phenyloxazole and the like, but the present invention is not limited thereto.

The photothermographic material of the present invention may contain an antifoggant. Mercury compounds are environmentally undesirable as effective antifoggants. Therefore, non-mercury antifoggants have been studied for a long time. Particularly preferred non-mercury antifoggants are the compounds disclosed in U.S. Pat. Nos. 3,874,946 and 4,756,999, -C (X1) (X2) (X3), where X1 and X
2 is a halogen, and X3 is a heterocyclic compound having one or more substituents represented by hydrogen or halogen).
Examples of suitable antifoggants are described in JP-A-9-2883.
The compounds described in paragraph Nos. [0030] to [0036] of No. 28 are preferably used. Another example of a preferred antifoggant is described in JP-A-9-90550.
No. Paragraph Nos. [0062] to [0063].

A sensitizing dye can be used in the photothermographic material of the present invention. As the useful sensitizing dye used in the present invention, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected. For example, JP-A-9-34078, JP-A-9-54409 and JP-A-9-8
No. 0679 are preferably used.

Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other forming layers. The photothermographic material of the present invention may contain, for example, a surfactant, an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, and a coating aid. These additives and the other additives mentioned above are RD
17029 (pp. 9-15, June 1978) can be preferably used.

The support used in the present invention is preferably a plastic film (eg, polyethylene terephthalate (PET), polycarbonate, polyimide, nylon, cellulose triacetate, polyethylene naphthalate) in order to prevent deformation of the image after development processing. . The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm. A heat-treated plastic support can also be used. The plastics to be employed include the above-mentioned plastics. The heat treatment of the support means a temperature at which the support is formed at a temperature lower than the melting point of the support and higher than the glass transition point by 30 ° C. or higher, preferably 35 ° C. or higher, before the photosensitive layer is coated. It is more preferable to heat at a temperature higher than 40 ° C. Known methods can be used for the film forming method and the undercoating manufacturing method of the support according to the present invention, and preferably, paragraphs [0030] to [0] of JP-A-9-50094 are used.
070].

In the present invention, a conductive compound such as a metal oxide and / or a conductive polymer can be contained in the constituent layer in order to improve the chargeability. These may be contained in any layer, but are preferably contained in an undercoat layer, a backing layer, a layer between the photosensitive layer and the undercoat, and the like. In the present invention, U.S. Pat.
The conductive compound described in No. 20 is preferably used.

[0104]

EXAMPLES In each of the apparatuses of the first to fourth examples of the embodiment, the apparatus was calibrated, the temperature control pattern was adjusted, and the following experiment was performed. In the experiment, for each of the films F-1 and F-2 shown below, 10 sheets of the film F having a size of 14 inches in width × 10 inches in length in the transport direction were thermally developed continuously, and then the exposed portion 12 was exposed.
A film F having a width of 17 inches and a length of 14 inches in the transport direction, which was exposed to a test pattern for density unevenness detection according to 0, was thermally developed, and the density unevenness in the width direction was observed. Note that the roller 230 and the belt 233 have 100 W / m /
The roller 230 was a solid roller having a diameter of 2 cm using a metal of K or more.

As a result of this experiment, in each case,
No practically problematic density unevenness was found.

Hereinafter, the film F that is preferably used in the above embodiment used in the above experiment will be described.

1. Film F-1 Silver halide-silver behenate dry soap was prepared by the method described in U.S. 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 was a 0.055 μm silver bromoiodide emulsion having 2% iodide.

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-chlorobenzozoyl) 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.

[0111]

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, manufactured by 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.

[0114] 2. Film F-2 This film is a film in which a photosensitive layer and a surface protective layer are provided in this order on one surface of a photographic support, and a back surface layer is provided on the other surface, and is a film prepared by the following method. .

[Preparation of Photographic Support] Concentration: 0.170
(Measured with a densitometer PDA-65 manufactured by Konica Corporation) A corona discharge treatment of 8 w / m 2 · min was applied to both sides of a 175 μm thick PET film colored blue.

(Preparation of Photosensitive Silver Halide Emulsion A) Water 9
6. Ossein gelatin having an average molecular weight of 100,000 in 00 ml
5 g and 10 mg of potassium bromide were dissolved at a temperature of 35 ° C.
After adjusting the pH to 3.0, 370 ml of an aqueous solution containing 74 g of silver nitrate, potassium bromide and potassium iodide in a molar ratio of (98/2) were equimolar to silver nitrate, and iridium chloride was converted to silver 1
An aqueous solution containing 1.times.10.sup.-4 mole per mole of pAg
It was added over 10 minutes by the controlled double jet method while maintaining at 7.7. Then 4-hydroxy-6
0.3 g of methyl-1,3,3a, 7-tetrazaindene
Was added, and the pH was adjusted to 5 with NaOH. The average particle size was 0.06 μm, the coefficient of variation of the particle size was 12%, and [10
0] Cubic silver iodobromide grains having an area ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant and desalting treatment, and then 0.1 g of phenoxyethanol was added thereto.
9, and adjusted to a pAg of 7.5 to obtain a photosensitive silver halide emulsion A.

(Preparation of Powdered Organic Silver Salt A) Behenic acid (111.4 g), arachidic acid (83.8 g) and stearic acid (54.9 g) were dissolved in 4720 ml of pure water at 80 ° C. Then while stirring at high speed 1.
Add 540.2 ml of 5M sodium hydroxide aqueous solution and add concentrated nitric acid
After adding 6.9 ml, the mixture was cooled to 55 ° C. to obtain a sodium organic acid solution. While the temperature of the above-mentioned organic acid sodium solution was kept at 55 ° C., the above-mentioned silver halide emulsion (containing 0.038 mol of silver) and 450 ml of pure water were added and stirred for 5 minutes. Next, 760.6 ml of a 1 M silver nitrate solution was added over 2 minutes, and the mixture was further stirred for 20 minutes, and water-soluble salts were removed by filtration. After that, washing with deionized water and filtration were repeated until the conductivity of the filtrate became 2 μS / cm, and filtration and centrifugal dehydration were performed. Obtained.

(Preparation of Photosensitive Emulsion Dispersion 1) 14.57 g of polyvinyl butyral powder (Butvar B-79 manufactured by Monsanto) was dissolved in 1457 g of methyl ethyl ketone, and 500 g of powdered organic silver salt A was gradually added while stirring with a dissolver-type homogenizer. And mixed well. Then, a media-type disperser (manufactured by gettzmann) filled with 80% 1mmZr beads (manufactured by Toray)
The dispersion was carried out at a peripheral speed of 13 m and a residence time in the mill of 0.5 minute to prepare a photosensitive emulsion dispersion liquid 1.

<Preparation of Infrared Sensitizing Dye Liquid> Infrared Sensitizing Dye 1
350 mg, 13.96 g of 2-chloro-benzoic acid, and 5-methyl-2
-2.14 g of mercaptobenzimidazole in methanol 73.
The solution was dissolved in 4 ml in the dark to prepare an infrared sensitizing dye solution.

[Preparation of Coating Solution for Photosensitive Layer] The above-mentioned photosensitive emulsion B
(500 g) and 100 g of MEK while stirring.
It was kept at ° C. Pyridinium hydrobromide perbromide (PHP, 0.45 g) was added and stirred for 1 hour. Further, calcium bromide (10% methanol solution 3.25m
l) was added and stirred for 30 minutes.

Next, sensitizing dye-1, 4-chloro-2-benzoylbenzoic acid and supersensitizer (5-methyl-2-
After adding a mixed solution (mercaptobenzimidazole) (mixing ratio 1: 250: 20, 0.1% methanol solution of sensitizing dye, 7 ml) and stirring for 1 hour, the temperature was reduced to 13%.
C. and stir for an additional 30 minutes.

While keeping the temperature at 13 ° C., 48 g of polyvinyl butyral is added and dissolved sufficiently, and then the following additives are added.

Developer (1,1-bis (2-hydroxy-3,5-dimethylphenyl) -2-methylpropane) 15 g Desmodu N3300 (Mobay Inc., aliphatic isocyanate) 1.10 g Phthalazine 1.5 g Tetrachlorophthale Acid 0.5 g 4-Methylphthalic acid 0.5 g After preparing the coating solution for the photosensitive layer, the temperature was kept at 13 ° C. and kept stagnant for the time shown in Table 1. <Back side coating> (Adjustment of back side coating liquid) Methyl ethyl ketone 830g
While stirring the cellulose acetate butyrate (E
asman Chemical Company, CAB381-20) 84.
2g, polyester resin (Vistic, Vitel)
4.5 g of PE2200B) was added and dissolved. 0.30 g of infrared dye-1 was added to the dissolved solution, and methanol 4 was added.
F-based activator dissolved in 3.2 g (Asahi Glass Co., Ltd., Surflon
KH40) and 2.3 g of an F-based activator (Dai Nippon Ink, Megafag F120K) were added, and the mixture was sufficiently stirred until dissolved. Finally, add 1 wt.
75g of silica (WRGrace, Syloid 64X6000) dispersed by a dissolver type homogenizer at a concentration of 75%
The mixture was added and stirred to prepare a coating solution on the back surface.

(Coating of back surface)
The coating liquid on the back surface was applied and dried by an extruder coater so that the dry film thickness became 3.5 μm. Drying temperature 100
It dried for 5 minutes using the drying air of 10 degreeC and the outdoor temperature of 10 degreeC.

<Surface protective layer> (Preparation of dispersion liquid) Cellulose acetate butyrate (E
asman Chemical Company, CAB171-15) 7.5
g, dissolved in 42.5 g of methyl ethyl ketone, into which calcium carbonate (Specialty Minerals,
Super-Pflex 200) was added, and the mixture was dispersed with a dissolver-type homogenizer at 8000 rpm for 30 minutes to prepare a calcium carbonate dispersion.

(Preparation of Coating Solution for Surface Protection Layer) Cellulose acetate butyrate (Eastman Chemical Co., CAB1) was stirred with 865 g of methyl ethyl ketone.
71-15) 96 g, and 4.5 g of polymethyl methacrylic acid (Rohm & Haas Co., Ltd., Paraloid A-21) were added and dissolved. 1.5 g of a vinyl sulfone compound HD-1, 1.0 g of benzotriazole, and an F-based activator (Asahi Glass Co., Ltd.
Surflon KH40) (1.0 g) was added and dissolved. Finally, 30 g of a calcium carbonate dispersion was added and stirred to prepare a coating solution for the surface protective layer.

<Coating on the Photosensitive Layer Side> The coating solution for the photosensitive layer and the coating solution for the surface protective layer were simultaneously multi-layer coated using an extrusion coater. The photosensitive layer has a coated silver amount of 2.4 g / m.
2. The surface protective layer is applied at a rate of
It was applied at a speed of 0 m. Thereafter, drying was performed for 10 minutes using a drying air having a drying temperature of 75 ° C. and a dew point temperature of 10 ° C.

[0128]

According to the present invention, it is possible to suppress the occurrence of density unevenness in the heat developing 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 diagram showing the drum outer peripheral surface temperature on the vertical axis and the length in the drum longitudinal direction on the horizontal axis.

FIG. 10 is a perspective view showing a second embodiment.

FIG. 11 is a view similar to FIG. 5, showing a third embodiment.

[Explanation of symbols]

 14 Drum 16 Roller 18 Frame 21 Guide bracket 28 Coil spring 30 Reinforcement member 32 Heater 34 Control electronic device 38 Flexible layer 100 Thermal developing device 110 Storage unit 120 Exposure unit 130 Developing unit 143 Supply roller pair 150A Cooling unit 150 Control unit 151 Motor 203, 213 Cooling roller 223 Cooling belt device F Film

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yasuaki Tamakoshi 591-7 Kamihirose, Sayama-shi, Saitama Konica Corporation F-term (reference) 2H112 AA03 AA11 BA23 BB03 BC10 BC19 BC22 BC24 BC40

Claims (12)

[Claims] 1. A heat developing method in which a heat developing material is heated by the heating member and thermally developed in a state where the heat developing material is substantially adhered to the surface of the heating member whose temperature is controlled to a predetermined heat developing temperature. In the apparatus, when continuously performing thermal development on a plurality of thermal developing materials, if at least a predetermined condition is satisfied, after thermal developing the previous thermal developing material and before thermally developing the next thermal developing material, A heat developing apparatus characterized in that the temperature of a heating member is once lowered and then heated to a predetermined heat development temperature. 2. Thermal development in which a heat developing material is heated by the heating member and thermally developed in a state where the heat developing material is substantially adhered to the surface of the heating member whose temperature is controlled to a predetermined heat developing temperature. In the apparatus, when continuously performing thermal development on a plurality of thermal developing materials, if at least a predetermined condition is satisfied, after thermal developing the previous thermal developing material and before thermally developing the next thermal developing material, A heat developing apparatus comprising: a cooling unit that cools an area that does not hold the heat development material in the previous heat development. 3. A method according to claim 1, wherein when a plurality of thermal developing materials are successively thermally developed, at least a predetermined condition is satisfied, and after a previous thermal developing material is thermally developed and before a next thermal developing material is thermally developed. ,
3. The heat developing apparatus according to claim 1, wherein at least a region of the heating member that holds the heat development material in the next heat development is brought into close contact with a high heat conductor. 4. 4. The method according to claim 3, wherein after the temperature of the heating member is lowered, at least a region of the heating member for holding a heat development material in the next thermal development is brought into close contact with the high thermal conductor. The thermal developing apparatus according to claim 1. 5. A heat developing method in which a heat developing material is heated by the heating member and thermally developed in a state where the heat developing material is substantially adhered to the surface of the heating member whose temperature is controlled to a predetermined heat developing temperature. In the apparatus, when continuously performing thermal development on a plurality of thermal development materials, if at least a predetermined condition is satisfied, at least before thermal development of the next thermal development material after thermal development of the previous thermal development material, A heat developing apparatus wherein a region of the heating member for holding a heat development material in the next heat development is brought into close contact with a high thermal conductor. 6. The heating member is a rotating body that rotates,
The heating device according to claim 1, further comprising: a supply unit configured to supply the heat development material to the heating member; and a discharge unit configured to discharge the heat development material from the heating member. Thermal development device. 7. The heat developing apparatus according to claim 6, wherein a plurality of sizes of heat developing materials having different lengths in the rotation axis direction of the heating member can be developed. 8. The thermal developing apparatus according to claim 6, wherein the heating member heats the thermal developing material at a developing temperature equal to or higher than the minimum developing temperature for a thermal developing time. 9. The heat developing apparatus according to claim 6, further comprising a rotatable roller biased by said heating member. 10. A thickness of 0.1 mm on a surface of the heating member.
The heat developing device according to any one of claims 6 to 9, wherein the elastic layer is provided. 11. The elastic layer has a thickness of 2 mm or less and a thermal conductivity of 0.4 W / mk or more.
The thermal developing device according to claim 10, further comprising a metal supporting member that directly or indirectly supports the elastic layer. 12. The heat-developable material contains photosensitive silver halide grains, an organic silver salt, and a silver ion reducing agent.
The thermal development is substantially not carried out at a temperature of 0 ° C. or less, and the thermal development is carried out at a temperature of 80 ° C. or more and a minimum development temperature or more. Heat development device.