JPH0336548A - Heat developing device - Google Patents

Abstract

PURPOSE:To obtain an excellent image on a photosensitive material by energizing a fluororesin sheet against a heating drum with an elastic material which has a curved surface along the peripheral surface of the heating drum. CONSTITUTION:The photosensitive material A is pinched between the heating drum 58 and fluororesin sheet 96 and energized against the heating drum 58 by the elastic material 94 which has the curved surface along the peripheral surface of the heating drum 58. Consequently, the photosensitive material A securely is brought hermetically into contact with the heating drum 58 while guided by guide means 60a - 60c. Further, the fluororesin sheet 96 has small friction resistance, so the photosensitive material is brought into excellent slide contact with the sheet without causing any trouble to the conveyance. Further, the photosensitive material carry-in side end part of the fluororesin sheet 96 is fixed to an elastic material supporting member 92 and the carry-out side end part is movable, so the sheet is never loosened when the photosensitive material is guided. Consequently, the photosensitive material is surely heat- developed by the heating drum and an excellent image is obtained on the photosensitive material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat developing device that thermally develops a photosensitive material by bringing the photothermographic material into contact with the circumferential surface of a rotationally driven heating drum.

[Conventional technology]

Various types of photosensitive materials are known in which a latent image formed on the photosensitive material is colored by heat development.

As a heat developing device, for example, there is a method in which a photosensitive material is wound around the peripheral surface of a rotationally driven heating drum, and the photosensitive material is brought into contact with the heating drum for a predetermined period of time while being conveyed to perform heat development.

In order to convey the photosensitive material along the circumferential surface of the heating drum,
For example, a plurality of nip rollers that come into contact with the circumferential surface of the heating drum are provided, and the heating drum and the nip rollers are rotationally driven.

A guide member is provided between the nip rollers around the heating drum so that the photosensitive material contacts the circumferential surface of the heating drum between the nip rollers, and the guide member guides the photosensitive material along the circumferential surface of the heating drum.

The guide member provided around the heating drum is provided with a gap between it and the heating drum that allows the photosensitive material to move, and is configured so that the photosensitive material is well conveyed along the circumferential surface of the drum. be.

[Problem to be solved by the invention]

However, since there is a predetermined gap between the heating drum and the guide member, when the photosensitive material is guided by the guide member,
The photosensitive material may separate from the circumferential surface of the heating drum. In this case, the photosensitive material is not heated sufficiently and good heat development is not performed.

On the other hand, when the support of a photosensitive material is made of a hygroscopic material such as paper, it absorbs a predetermined amount of moisture in the air, and also absorbs a large amount of moisture in a high-temperature atmosphere.

When a photosensitive material containing such moisture is subjected to heat treatment using a heat developing device, the moisture in the photosensitive material evaporates, but the moisture that did not evaporate remains in the photosensitive material that contained a large amount of moisture. . Then, due to the influence of the remaining moisture, the photosensitive material is not heated uniformly, and the density of the image obtained by development is not constant, and wrinkles occur in the photosensitive material.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a heat developing device that can heat a photosensitive material well with a heating drum and can obtain a good image.

[Means and Effects for Solving the Problems] The above object of the present invention is to provide a heating drum in a heat developing device that thermally develops a photosensitive material by bringing the heat-developable photosensitive material into contact with the circumferential surface of a rotationally driven heating drum. an elastic material having a curved surface along the circumferential surface of the heating drum; a support member supporting the elastic material; The photosensitive material guiding means is provided with a fluororesin sheet whose surface side is covered and overlapped with the elastic material, and whose end on the photosensitive material loading side is fixed to a support member, and the elastic material urges the sheet against the heating drum. This is achieved by a heat developing device.

That is, the photosensitive material is sandwiched between the heating drum and the fluororesin sheet, and the elastic material having a curved surface along the circumferential surface of the heating drum urges the fluororesin sheet against the heating drum, so that the photosensitive material is guided by the heating drum. while being guided by the heating drum. Furthermore, since the fluororesin sheet has low frictional resistance, even if the photosensitive material comes into close contact with the sheet, it can be in good sliding contact without interfering with conveyance.

Furthermore, since the photosensitive material loading side end of the fluororesin sheet is fixed to the elastic material support member, and the unloading side end is movable,
The sheet does not loosen when guiding the photosensitive material, the sheet can evenly urge the photosensitive material against the heating drum, and the photosensitive material is reliably brought into close contact with the heating drum.

Therefore, the photosensitive material is reliably heat-developed by the heating drum, and a good image can be obtained on the photosensitive material.

Further, the above-mentioned object of the present invention is to provide a heat developing device that heat-develops a photosensitive material by bringing the photothermographic material into contact with the circumferential surface of a rotationally driven heating drum. This is achieved by a heat developing device equipped with a conveying means for pinching and conveying the material, and a photosensitive material guiding means having a fluororesin sheet stretched in contact with the circumferential surface of a heating drum.

That is, by biasing and guiding the photosensitive material toward the heating drum by the tension of the fluororesin sheet, the photosensitive material is reliably brought into close contact with the heating drum while being guided by the guide means. Furthermore, since the fluororesin sheet has low frictional resistance, even if the photosensitive material comes into close contact with the sheet, it can be in good sliding contact without interfering with conveyance.

Therefore, the photosensitive material is reliably heat-developed by the heating drum, and a good image can be obtained on the photosensitive material.

Further, the above-mentioned object of the present invention is to provide a heat developing device that heat-develops a photosensitive material by bringing the photothermographic material into contact with the circumferential surface of a rotationally driven heating drum. and a photosensitive material guiding means curved along the circumferential surface of a heating drum, and the conveying means in the photosensitive material loading section is a hygroscopic roller equipped with a heat generating means. achieved.

In other words, a hygroscopic heating roller equipped with a heat generating means,
By conveying the photosensitive material around the circumferential surface of the heating drum, the photosensitive material is heated by the hygroscopic heating roller before being heated by the heating drum. Then, some of the water contained in the photosensitive material evaporates and is absorbed by the hygroscopic heating roller, and the remaining water evaporates when heated by the heating drum, so the photosensitive material is uniformly unaffected by the water. heated to.

Therefore, the photosensitive material can be reliably heat-developed by the heating drum without wrinkles, and a good image can be obtained on the photosensitive material.

The heat-developable photosensitive material of the present invention may be any type of recording method such as exposure and fixing as long as it requires heat treatment.

As a heat-developable photosensitive material, for example, JP-A-59-190
No. 886 discloses a diazo-sensitive material having a genus containing microcapsules containing a diazonium salt, a coupler, and a base on a support. A latent image corresponding to the original is created by exposure to light and developed by heating.

[Embodiment]

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

FIG. 1 is a schematic diagram of a copying apparatus using a diazo photosensitive material, and this copying apparatus is configured to color an image on the photosensitive material by dry development.

The copying device includes a document transport section 32 for carrying in and discharging a document C and for repeatedly circulating the same document C within the device, and an exposure section 34 for exposing an image onto a photosensitive material A superimposed on the document C. and a developing section 36 that heats and develops the document C after exposure.

The document conveyance section 32 includes a plurality of conveyance belts 40 hooked and rotated in parallel around the circumferential surface of a hollow guide drum 38, and further includes another belt 42 stretched across the belt 40, so that both belts 40 By rotationally driving the .42, the document C is held and conveyed.

A cassette 2 containing photosensitive material A is loaded below the document transport section 32 . The photosensitive material A in the cassette 2 is
The paper feed roller 3 is moved in time with the document C being transported.
0, the originals are fed one by one to the stacking section 44, and the originals C
It is superimposed with.

The photosensitive material A overlapped with the original C is conveyed to the exposure section 34 by the conveyance roller 30.

The exposure section 34 includes an exposure lamp 48 containing a fluorescent lamp 46, the exposure lamp 48, and four belt support rollers 50.
The exposure lamp 48 is supported by a belt 52 that is wrapped around approximately 3/4 of the circumferential surface of the exposure lamp 48. Then, the exposure lamp 48 and the belt 52 are driven to rotate, and while the document C and the photosensitive material A overlapped between the exposure lamp 48 and the belt 52 are conveyed, the light from the exposure lamp 48 is used. An original image is projected onto the photosensitive material A to form a latent image.

The exposed document C and photosensitive material A are sucked in opposite directions by a suction means (not shown) in the peeling section 54 and peeled off. The photosensitive material A is separated from the original C in the peeling section 54.
After being peeled off, it is transported to the developing section 36.

The developing section 36 includes a hollow cylindrical heating drum 58 having a halogen lamp 56 therein, and three conveyance rollers 60 that come into contact with the circumferential surface of the heating drum 58. A guide means 62 for guiding the photosensitive material A in contact with the circumferential surface of the heating drum 58 is provided between the conveyance rollers 60 . The photosensitive material A is then heated and developed while being held and conveyed by the heating drum 58 and the conveyance roller 60, and the latent image on the photosensitive material A is visualized.

In the developing section 36, the photosensitive material A may be transported by an endless belt wound around the circumferential surface of the heating drum 58 instead of the transport roller 60.

The developed photosensitive material A is discharged from the discharge port 64 and slides onto the discharge tray 66.

On the other hand, the original C that has been separated from the photosensitive material A is transferred to the conveyor belt 40.
or the guide drum 38.
, and is used again for copying through the same process as described above.

FIG. 2 is a sectional view of the heat developing section 36 according to the first embodiment of the present invention.

Three conveyor rollers 60a-w are provided on the circumferential surface of the heating drum 58.
The first conveying roller 60a, which is in contact with the first conveying roller 60a and which is located at the entrance to the heating drum 58, is a hygroscopic roller made of sponge or the like, and is equipped with a heater 90 inside. Further, the second conveyance roller 60b and the third conveyance roller 60c are made of hard rubber.

The guide means 62 provided between the first conveyance roller 60a and the second conveyance roller 60b includes an elastic material support member 92 curved along the circumferential surface of the heating drum 58 and a curved surface along the circumferential surface of the heating drum 580. It consists of an elastic material 94 and a sheet 96. The support member 92, elastic material 94, and sheet 96 are formed to have a width slightly larger than the width of the photosensitive material A. The inner surface of the support member 92 is covered with an elastic material 9 such as felt or soft rubber.
4 is fixed. Further, a fluororesin sheet 96 such as polytetrafluoroethylene (eg, Teflon@) is provided to cover the inner surface of the elastic material 94, and an end portion of the sheet 96 on the carry-in side is fixed to the support member 92. The sheet 92 is
Only the carrying-out side end is fixed, and it is not fixed to the elastic member 94 and is movable relative to the elastic member 94, and the other carrying-out side end is also movable.

The carry-in side end of the elastic member 94 is located slightly in the carry-out direction from the sheet-fixed end of the support member 92, and the carry-in side end of the sheet 96 is inclined. Therefore, the conveyance roller 6
The photosensitive material A conveyed by 0a easily enters between the heating drum 58 and the sheet 96 along the inclined surface of the sheet 96.

In addition, the second conveyance roller 60b and the third wt conveyance roller 60c
The same guide means 62 is also provided between.

The photosensitive material A supplied to the heat developing section 36 is first nipped and conveyed by the first conveyance roller 60a and the heating drum 58. The temperature of the heating drum 58 is maintained at 150° C. by the halogen lamp 56 in advance, and the temperature of the heating drum 58 is maintained at 150° C. by the halogen lamp 56.
The temperature is maintained at °C by a heater 90. The photosensitive material A held between the first conveyance roller 60a and the heating drum 58 is heated by the first conveyance roller 60a, and part of the water contained in the support evaporates.

The evaporated moisture is absorbed by the hygroscopic first conveying roller 60a, but the third weight conveying roller 60c dries after conveying the photosensitive material A and before the subsequent photosensitive material A is supplied.

Thereafter, the photosensitive material A is transferred to the heating drum 5 by the guide means 62.
8. Heat development is performed while being guided along the circumferential surface.

When the photosensitive material fAA enters between the heating drum 58 and the sheet 96, even if the leading edge of the photosensitive material A is lifted from the heating drum 58, the leading edge of the photosensitive material A will move along the inclined surface of the sheet 96. It is guided to the heating drum 58. When the photosensitive material A is guided by the guide means 62, the photosensitive material A
is brought into close contact with the heating drum 58 by the sheet 96.

The support member 92 is fixed in position with respect to the heating drum 5, and the elastic material 94 provided on the support member 92 is attached to the sheet 96.
is applied to the heating drum 58, so the heating drum 58
The photosensitive material A sandwiched between the sheet 96 and the sheet 96 is closely guided to the heating drum 58 and heat-developed. The force exerted on the sheet 96 by the elastic member 94 can be adjusted by the material and thickness of the elastic member 94 and the attachment position of the support member 92 to the heating drum 58.

Since the sheet 96 is made of fluororesin, the heating drum 5
When the photosensitive material A moves together with the heating drum 58 by the rotation of the photosensitive material 8 and the conveying roller 60 a = c, the photosensitive material A smoothly slides into contact with the sheet 96 .

Furthermore, since the end of the sheet 96 on the unloading side is not fixed to the support member 92, the sheet 96 is always subjected to force in the unloading direction while guiding the photosensitive material A. Therefore, the sheet 96 does not loosen, and the sheet 96 can uniformly bring the photosensitive material A into close contact with the heating drum 58 due to the elastic force of the elastic member 940.

Note that the elastic material 94 only needs to have a curved surface along the heating drum 58, and the shape of the elastic material 94 is not limited to that illustrated. Similarly, the shape of the elastic material support member 92 is not limited to that illustrated.

FIG. 3 is a sectional view of a heat developing section 36 according to a second embodiment of the present invention. Note that in FIG. 3, the same reference numerals as in FIG. 2 indicate the same parts.

This embodiment differs from the first embodiment in that the elastic member 94 is omitted and that the sheet 96 is fixed to the support member 92, but the other structures are the same. Only the different parts of the configuration will be explained below.

The support member 92 has a curved shape, and the length of the fluororesin sheet 96 in the conveying direction is shorter than the curved length of the support member 92.
Both ends in the transport direction are fixed to support members 92. Then, when the support member 92 is fixed in position relative to the heating drum 58, the sheet 96 contacts the heating drum 58 and becomes tense. Therefore, the sheet 96 is brought into close contact with the heating drum 58 due to its own tension. The tension of the sheet 96 is adjusted by the fixed position of the support member 92 with respect to the heating drum 58.

While the photosensitive material A is sandwiched and guided by the heating drum 58 and the sheet 96, it is uniformly brought into close contact with the heating drum 58 due to the tension of the sheet 96, and is heated and developed.

Note that the configuration for tensioning the sheet 96 is not limited to the above-mentioned configuration, and any structure may be used as long as the ends of the sheet 96 can be fixed at respective appropriate positions and stretched. Therefore, the shape of the support member 92 is not limited to that illustrated.

In the above two embodiments, the second conveyance roller 60b is omitted, and the first conveyance roller 60a to the third vi conveyance roller,
A guide means 62 having the same configuration as above may be provided to guide the photosensitive material A up to 760C.

〔Effect of the invention〕

According to the present invention, the photosensitive material is sandwiched between the heating drum and the fluororesin sheet, and the elastic material having a curved surface along the circumferential surface of the heating drum urges the fluororesin sheet against the heating drum. The material is ensured to be in close contact with the heating drum while being guided by the guiding means. Furthermore, since the fluororesin sheet has low frictional resistance, even if the photosensitive material comes into close contact with the sheet, it can be in good sliding contact without interfering with conveyance. In addition, since the end of the fluororesin sheet on the photosensitive material loading side is fixed to the elastic material support member, and the unloading side end is movable, the sheet does not loosen when guiding the photosensitive material.
The sheet can uniformly urge the photosensitive material against the heating drum, and ensures that the photosensitive material is in close contact with the heating drum.

Therefore, the photosensitive material is reliably heat-developed by the heating drum, and a good image can be obtained on the photosensitive material.

Furthermore, by biasing and guiding the photosensitive material toward the heating drum by the tension of the fluororesin sheet, the photosensitive material is reliably brought into close contact with the heating drum while being guided by the guide means. Furthermore, since the fluororesin sheet has low frictional resistance, even if the photosensitive material comes into close contact with the sheet, it can be in good sliding contact without interfering with conveyance.

Therefore, the photosensitive material is reliably heat-developed by the heating drum, and a good image can be obtained on the photosensitive material.

Further, by conveying the photosensitive material to the circumferential surface of the heating drum by a hygroscopic heating roller equipped with a heat generating means, the photosensitive material is heated by the hygroscopic heating roller before being heated by the heating drum. Then, some of the moisture contained in the photosensitive material evaporates and is absorbed by the hygroscopic heating roller, and the remaining moisture evaporates when heated by the heating ram, so the photosensitive material is not affected by moisture. Heats evenly.

Therefore, the photosensitive material can be reliably heat-developed by the heating drum without wrinkles, and a good image can be obtained on the photosensitive material.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a copying apparatus to which the present invention is applied, FIG. 2 is a cross-sectional view of a first embodiment of the present invention, and FIG. 3 is a cross-sectional view of a second embodiment of the present invention. Code in the figure: Figure 2 Figure procedural amendment December 4, 1999

Claims (1)

[Scope of Claims] (1) In a heat developing device that heats and develops a photosensitive material by bringing the photosensitive material into contact with the circumferential surface of a rotationally driven heating drum, the photosensitive material is placed between the circumferential surface of the heating drum and the photosensitive material. It is provided with a conveying means for pinching and conveying, and further includes an elastic material having a curved surface along the circumferential surface of the heating drum, a support member supporting the elastic material, and a supporting member that covers the curved surface side of the elastic material and superimposes it on the elastic material. A heat developing device (2) is rotatably driven, comprising a photosensitive material guide means consisting of a fluororesin sheet whose end on the photosensitive material feed side is fixed to a support member, and an elastic material urges the sheet against a heating drum. In a heat developing device that heat-develops a photosensitive material by bringing the photosensitive material into contact with the circumferential surface of a heating drum, the photosensitive material is conveyed by sandwiching the photosensitive material between the circumferential surface of the heating drum and the circumferential surface of the heating drum. A heat developing device (3) equipped with a photosensitive material guiding means having a fluororesin sheet stretched in contact with the surface (3) The photothermographic material is brought into contact with the circumferential surface of a rotationally driven heating drum to heat develop the photosensitive material. The heat developing device is equipped with a conveying means for conveying the photosensitive material while sandwiching it between the circumferential surface of the heating drum and a photosensitive material guide means curved along the circumferential surface of the heating drum. A heat developing device in which the means is a hygroscopic roller equipped with a heat generating means