JP2001147511A - Heat developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developing device having a simple and compact structure and capable of stably keeping the uniform temperature distribution of a material heating means for a long time. SOLUTION: In the heat developing device for performing the heat development of the photosensitive heat developable material by bringing into contact with the material heating means supported at both ends by a side plate, and end part heating means for heating both end parts of the material heating means inside the side plate is arranged.

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 for heating and developing a photosensitive heat-developable recording material, and more particularly, to a material heating means for heating the photosensitive heat-developable recording material. The present invention relates to a heat developing device.

[0002]

2. Description of the Related Art A latent image is formed by exposing a sheet of photosensitive heat-developable recording material (hereinafter referred to as a heat-sensitive material) imagewise with a laser beam or the like, and then the entire surface of the sheet is heated to develop. A heat developing device for performing the heat development is known. Heating is performed by contacting or sliding on and conveying a sheet heater or a drum heater. At least one of the roller pairs is a heating roller, and heating is performed by nipping and conveying between the plurality of roller pairs. Type is common.

In the latter type of heat developing device using a heating roller,
Each heating roller is rotatably fixed at both ends to the side plate, and is arranged in parallel in the transport direction of the heat-sensitive material. This heating roller usually has a sheath heater or a halogen heater built in a hollow metal roller.
Generally, the surface of the metal roller is covered with rubber as a lining.

[0004] However, such a heating roller has a large heat radiation from an unlined shaft end, and heat can easily escape from both ends in contact with the side plate. Tend to be low. This temperature difference is undesirable because it causes unevenness in the developability of the heat-sensitive material.

In order to eliminate this temperature difference, the amount of heat generated at the end of the heater is made larger than that at the center, the heaters having different amounts of heat at the center and both ends of the heating roller are built in, A method has been proposed in which the thickness of the metal core is changed only at both ends and the rubber thickness of the lining is changed only at both ends. However, these methods are not preferable because the processing of the heating roller becomes complicated. In addition, in the case of a heating roller having such a complicated processing, the balance of the amount of heat generated at the center and both ends of the heating roller tends to be lost with the use time of the heater, and the life of the heater is shortened. In addition, it is difficult to maintain a uniform temperature distribution between the center and the end of the heater over a long period of time.

Further, if the both ends of the heating roller, whose temperature is lowered, are left as margins without being used for heating the heat-sensitive material, an unnecessary large heating roller is required, and the apparatus becomes large.

In order to prevent heat from being radiated from both ends of the heating roller, it is conceivable that the ends have an excessively heat-insulating structure. However, the size and cost of the apparatus also increase.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a heat developing apparatus which has a simple and compact structure, is stable for a long time, and can maintain a uniform temperature distribution of the material heating means. To provide.

[0009]

The object of the present invention has been attained by the following constitutions.

[0010] 1. In a heat developing apparatus for performing heat development of the photosensitive heat-developable recording material by contacting the photosensitive heat-developable recording material with a material heating means having both ends supported on a side plate, A heat developing device, comprising end heating means for heating both ends.

2. The material heating means has a plurality of heating rollers arranged in parallel, a pressing roller paired with the plurality of heating rollers is provided facing the heating roller,
While the photosensitive heat development recording material is sandwiched between the heating roller and the pressing roller, the heat development of the photosensitive heat development recording material is performed by transporting the plurality of heating rollers in a direction arranged in parallel. 2. The thermal developing device according to the above item 1, wherein

3. 3. The heat developing device according to the above item 2, wherein the heating roller has a built-in halogen heater.

4. 4. The thermal developing apparatus according to claim 1, wherein the end heating unit is a sheathed heater.

5. 5. The thermal developing apparatus according to claim 1, wherein the end heating means is a cartridge heater inserted in an aluminum block.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.

FIG. 1 is a schematic sectional view of the heat developing apparatus of the present invention. In the present embodiment, the type in which the sheet is nipped and conveyed by a plurality of roller pairs has been described. However, of course, the type in which the sheet is brought into contact with a sheet heater or a drum heater may be used as long as both ends are supported by side plates. Needless to say, this is included in the present invention. However, since the thermal developing device of the type of nipping and transporting by a plurality of roller pairs has a plurality of heating rollers as material heating means, it is difficult to efficiently control all the heating rollers to a uniform temperature, and The surface area of the heating roller is increased as a whole, and at the same time, the area of the shaft end portion that is not related to direct thermal development is also increased. It can be said that

In the drawing, reference numeral 1 denotes a heat developing device, 2 denotes a heat-sensitive material, 100 denotes a heat-development unit, 200 denotes a leg supporting the heat-development unit 100, and 300 denotes a film containing the heat-developable heat-sensitive material. It is a basket. In the heat developing unit 100, 110 is a pressing roller, 130 is a heating roller as a material heating unit, 150 is a heat insulating material, and 170 is the heat developing unit 10.
It is a spacer for filling the gap of 0 and reducing the air to be wasted.

The roller diameters of the pressing roller 110 and the heating roller 130 are both 48 mmφ in the present embodiment, and the length in the width direction (the distance from the near side to the far side in the drawing) is 75 mm.
0 mm. The distance between adjacent rollers in the direction of transport of the heat-sensitive material is 60 mm. Although not shown in FIG. 1, a guide plate serving as a bridge is provided between adjacent heating rollers, and the surface temperature of each heating roller is set at the bottom of the heat developing unit 100. It is preferable that a temperature sensor to be detected is attached so that the heating roller 130 as a material heating means can be controlled so as to always generate heat at a constant temperature.

A heating power source for causing the heating roller 130 to generate heat, a pressing roller 110 for transporting the heat-sensitive material 2 in the direction of the arrow, and a rotation driving means for the heating roller 130 are provided.
It is housed in the leg 200 (not shown).

The heat developing section 100 is divided into three areas from a left side in the figure, a pre-heating section A, a main heating section B, and a post-heating section C.
It is set differently from 120 ° C. (there is a temperature gradient from upstream to downstream) (pre-heating section A), 120 ° C. (main heating section B), and 110 ° C. (post-heating section C). This corresponds to the design of the heat-sensitive material, and whether to divide into a plurality of areas and the heating temperature depend on the type of the heat-sensitive material.

Since it is important for each of the pre-heating section A and the main heating section B to start the heat development to keep the heat generation temperature of the heating roller with a small error, the heat insulating material 150 is filled in the wall surface.

FIG. 2 is a schematic view showing one embodiment of the heating roller. FIG. 2A is a schematic sectional view of a pair of a pressing roller and a heating roller, and FIG. 2B is an exploded perspective view of the heating roller. In FIG. 2, only the vicinity of one end of the roller is shown, but a portion not shown may be considered to be a symmetrically folded portion of the illustrated portion. The heat-sensitive material is sandwiched in the gap between the pressing roller 110 and the heating roller 130, and is conveyed from the near side of the drawing to the far side (or from the far side to the near side).

In the heating roller 130, the end of the hollow roller 133 made of metal having a high thermal conductivity such as aluminum is
The shaft diameter is slightly smaller than the portion heated by contact with the heat-sensitive material.
It is rotatably mounted via a connector 05. The surface of the portion of the heating roller 130 that heats the heat-sensitive material may be made of rubber,
The elastic lining 135 is covered. When the lining 135 has elasticity, the lining 135 can flexibly contact the conveyed heat-sensitive material, and has an advantage that the surface of the heat-sensitive material is hardly damaged. The thermal conductivity of the lining 135 with respect to the hollow roller 133 is less than 1/1000, preferably 10,000.
It is less than one part.

The halogen heater 131 inserted in the internal space of the hollow roller 133 is a heat source for causing the heating roller 130 to generate heat. The interior of the hollow roller 133 is preferably painted black so that heat rays (such as infrared rays) can be efficiently absorbed. In the present embodiment, the halogen heater 131 is set to 200 W for the heating roller of the main heating section. The halogen heater 131 is not subjected to special processing such as changing the heat generation balance between the end and the center of the heating roller 130. Although the heat source of the material heating means of the present invention is not limited to this, the halogen heater can heat the inside of the hollow roller 133 painted black by a heat ray, in addition to heat transfer by air. Further, since the heat generation temperature can be maintained with a small error, it can be preferably used.

The exposed portion of the hollow roller 133 having a shaft diameter slightly smaller than the portion of the end of the heating roller 130 where the heat-sensitive material is heated is heated by the end heating means 137. The end heating means 137 includes the hollow roller 13.
3 and a heat-insulating cover 137d that covers the sheathed heater 137h and prevents heat dissipation. The heat source of the end heating means is not limited to this sheathed heater, but does not require more precise temperature control than the heat source of the material heating means described above. Since a suitable heater is preferable, a sheathed heater can be preferably used. The amount of heat generated by the sheath heater 137h at this time is obtained by multiplying the heat generation rate required to maintain the temperature after the halogen heater 131 as a material heating unit reaches a desired temperature by the heat release rate from the halogen heater 131. Or more. For example, if the heat generation ratio for maintaining the temperature of the halogen heater of 200 W is 30% and the heat radiation ratio is 3%, 200 W × 0.3 × 0.03 = 1.8 W. Those can be used as edge heating means. The end heating means does not need precise temperature control, but it is preferable to provide safety measures such as an overheat switch. Further, since the temperature of the heating roller of the pre-heating unit A and the temperature of the heating roller of the main heating unit B are different, when the same heater is used as an end heating means at the end of these heating rollers, the temperature is adjusted to the optimum temperature. Control (temperature control) is required. For the heat insulating cover 137, a foaming resin such as polyurethane, ceramic, or the like can be preferably used. By heating the end of the hollow roller 133 inside the side plate 101 using the end heating means 137,
It is possible to easily solve the problem that the heat is transmitted along the side plate 101 and the temperature of both ends of the heating roller 130 is lowered. Providing the end heating means inside the side plate 101 increases the efficiency of preventing heat radiation from both ends of the heating roller 130, and the side plate 101 or the outside of the side plate 101 (side plate 10).
By providing an excessive heat insulating structure on the side opposite to the one hollow roller 133), the cost and the size of the apparatus are not increased.

FIG. 3 is a schematic view showing another embodiment of the end heating means of the heating roller. FIG. 3A is a schematic sectional view when the heating roller is viewed from above, and FIG. 3B is an exploded perspective view. FIG. 3 also shows only the vicinity of one end of the heating roller similarly to FIG. The side plate 101, the bearing 105, the halogen heater 131, the hollow roller 133, and the lining 135 are the same as those in FIG.

In this embodiment, as the end heating means, an aluminum block 1 having a cartridge heater 139h inserted therein is used.
39b is used. The aluminum block 139b has a concave portion 139c that can receive the end of the heating roller 130, and is close to at least half of the surface area of the portion where the hollow roller 133 at the end of the heating roller 130 is exposed, so that the efficiency is improved. It is designed to conduct heat. The lower part of the recess of the aluminum block 139b is the cartridge heater 1
It has a hole 139k into which 39h can be inserted. A cartridge heater 139h containing a heating wire or the like in a cartridge is inserted into the hole 139k of the aluminum block 139b, and the heating roller 1 is inserted through the aluminum block 139b.
Heat the end of 30. Also, aluminum block 139b
A heat insulating material 150 was attached around the aluminum block 139b so as not to dissipate heat and waste energy. This may be easily detachable as a heat insulating case. In this embodiment, it is not necessary to provide the number of heating rollers as the cartridge heater as the end heating means.

The heat-sensitive material to be heat-developed by the heat-developing apparatus of the present invention is described in, for example, US Pat. Nos. 3,152,904 and 3,457,075; Morgan
an) "Dry silver photographic material (Dry Si
Lever Photographic Material
l) "and D.E. Morgan and B.A. Shelly Processed Sil by Shelly
VerSystems) "(Imaging Pros and Materials (Imaging Pro)
sessesand Materials) Neble
tte 8th edition, Sturge, V.T. Walworth, A .; Shep (Sh
e.p.), page 2, 1969).

[0029]

According to the present invention, it is possible to provide a heat developing apparatus which has a simple and compact structure, and can stably maintain the temperature distribution of the material heating means uniformly for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a heat developing apparatus of the present invention.

FIG. 2 is a schematic view illustrating one embodiment of a heating roller.

FIG. 3 is a schematic view showing another embodiment of the end heating means of the heating roller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thermal developing device 2 Thermal material 100 Thermal developing unit 101 Side plate 105 Bearing 110 Press roller 130 Heating roller 131 Halogen heater 133 Hollow roller 135 Lining 137h Sheath heater 137d Heat insulating cover 139b Aluminum block 139h Cartridge heater 150 Heat insulating material

Claims (5)

[Claims] 1. A thermal developing apparatus for thermally developing a photosensitive heat-developable recording material by bringing the photosensitive heat-developable recording material into contact with a material heating means having both ends supported by a side plate, wherein: A heat developing apparatus, wherein end heating means for heating both ends of the material heating means are provided. 2. The heating device according to claim 1, wherein the material heating unit includes a plurality of heating rollers arranged in parallel, and a pressing roller paired with the plurality of heating rollers is provided to face the heating roller. Between the roller and the photosensitive thermal development recording material, while performing the thermal development of the photosensitive thermal development recording material by transporting the plurality of heating rollers in a direction arranged in parallel while sandwiching the photosensitive thermal development recording material. The thermal developing device according to claim 1, wherein 3. The heat developing apparatus according to claim 2, wherein the heating roller has a built-in halogen heater. 4. The thermal developing apparatus according to claim 1, wherein said end heating means is a sheathed heater. 5. The heat developing apparatus according to claim 1, wherein said end heating means is a cartridge heater inserted into an aluminum block.