JP2000284457A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To comparatively stably obtain an excellent image by suppressing the occurrence of defective development by means of preventing the occurrences of stripe-like soiling and stripe-like density unevenness by bringing a photosensitive heat developable material into close contact with the surface of a heating member so that two opposed sides cut better than other two opposed sides are set on a side in the rotating direction of the heating member. SOLUTION: Film F possesses a cut surface R cut well by a rotary cutter and the cut surface D comparatively badly cut by a sheet cutting cutter. The film F is stacked so that two opposed sides of the cut surface R of the film F are set as a top and a rear end in a feeding direction H and two opposed sides of the cut surface D are set on the side in the feeding direction H. The film F is supplied to a pair of feeding rollers 112 by a suction unit 111. Then, when two opposed sides of the cut surface R are set as the top and the rear end in the feeding direction H, the occurrence of a foreign matter due to impact caused at the time of entering the pair of the feeding rollers 112 is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rotating heating member,
A guide member provided around the heating member, for urging the photosensitive thermal development material onto the surface of the heating member; and a heat source for thermally developing the photosensitive thermal development material by heating the photosensitive thermal development material with the heating member. The present invention relates to an image forming apparatus including a developing unit.

[0002]

2. Description of the Related Art Sheet-like films, which are photosensitive heat-developable materials deposited on a tray, are taken out one by one using a suction cup or the like, and the taken-out films are conveyed to an exposure section, and a laser beam or the like is produced based on an image signal. 2. Description of the Related Art An image forming apparatus that exposes a photosensitive surface of a film to form a latent image, and then conveys the film to a heat developing unit and heat develops to obtain a visible image is provided on the market.

[0003]

However, in such an apparatus, there is a problem that image quality is deteriorated, for example, streak-like dirt adheres or streak-like density unevenness occurs.

[0004] The present invention has been made in view of the above problems, and has as its object to suppress the occurrence of such deterioration in image quality.

[0005]

An example of a film (photosensitive material) used in such an image forming apparatus will be described with reference to FIGS. 8 and 9. FIG. Hereinafter, this example film is simply referred to as a film.

FIG. 8 is a cross-sectional view of the film, schematically showing a chemical reaction in the film during exposure, and FIG. 9 is a cross-sectional view of the film, showing the chemical reaction in the film during heating (development). FIG. 2 is a view schematically showing a target reaction.

The film is formed by applying and drying a photosensitive layer 2 mainly composed of a heat-resistant resin binder on one surface of a support 1 made of a heat-resistant resin. Is formed by coating and drying. In the photosensitive layer, silver behenate (Beh. Ag)
And a reducing agent and a toning agent. On the other surface of the support 1, a back surface layer 4 mainly composed of a heat-resistant resin binder is formed.

When the film is irradiated with laser light L from the exposed portion during exposure, as shown in FIG. 8, silver halide is exposed to the area irradiated with the laser light L to form a latent image. Is done. Then, when the film is heated, as shown in FIG. 9, 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, a reducing agent acts with the exposed silver halide grains as nuclei, and it is considered that a silver image is formed by a chemical reaction. As described above, the film has photosensitive silver halide grains, an organic silver salt, and a silver ion reducing agent, and is not substantially thermally developed at a temperature of 40 ° C. or lower. Thermal development is performed at a temperature not lower than the minimum developing temperature of not lower than 80 ° C.

The film is manufactured through, for example, steps shown in FIGS. 10A and 11A. First, as shown in FIG. 10A, a wide film roll in which a photosensitive layer 2 and a protective layer 3 are applied on one surface of a support 1 and a back surface layer 4 is applied on the other surface. The original roll 5 is slit into a desired width using a rotary cutter 6 to produce a roll 7 having a narrow width (for example, 14 inches). This usually results in good sharpness.

FIG. 10B shows an enlarged cross section of a cut portion of an example of such a rotary cutter 6. The rotary cutter 6 slits the film F where the holding roller 8 is held. A groove 84 is provided in a region of the holding roller 8 facing the rotary cutter 6 in a circumferential shape. While rotating the rotary cutter 6, the film F is rotated at substantially the same speed as the peripheral speed of the holding roller 8.
The film F is cut and slit while the edge of the rotary cutter 6 enters the groove 84 while the edge of the rotary cutter 6 is in sliding contact with the wall of the groove 84. This results in very good sharpness.

Next, as shown in FIG. 11A, the film unwound from the roll 7 is conveyed, cut using a cutting cutter (guillotine cutter) 9, and cut into a desired size (for example, 17 inches, for example). 14 inch, 11 inch) sheet-like film F is manufactured.

In general, the cut surface D (see FIG. 12A) of the film F cut by the cutting cutter 7 has burrs or the like at the corners (ridges) of the cut surface. The cut surface R of the film F cut by using
(See (b))).

In the case of a photosensitive heat developing material, the photosensitive layer 2
Contains an organic silver salt and a heat-resistant resin as a main component,
Since the photosensitive layer 2 is hard and brittle, the photosensitive layer 2 may be separated from the support layer 1 at the cut surface D as shown in FIG.

FIG. 11B is a cross-sectional view of an example of such a cutting device that is relatively sharp. A groove 94 is provided on a base 92 having a flat upper surface on which the film F is mounted, and into which the leading end of the cutting cutter 9 enters. When the leading end of the cutting cutter 9 enters the groove, the cutting edge of the cutting cutter 9 is It comes in sliding contact with the wall. Then, the pressing member 91 that presses the film F from the same direction as the cutting cutter 9 presses the film F when the cutting cutter 9 cuts the film F so that burrs are not formed at the time of cutting.

However, even in such a cutting apparatus, the film F cut by the rotary cutter 6 is used.
The cutting surface R (see FIG. 12B) has a poorer cutting performance.

In the heat developing section of the image forming apparatus, the photosensitive heat developing material is formed such that two opposing sides, which are less sharp than the other two opposing sides, are lateral to the direction in which the heating member rotates. When the is adhered to the surface of the heating member, as shown in FIG. 13, linear debris adheres to the peripheral surface of the heating member (the drum 14 in FIG. 13), a plurality of linear debris adheres, and the width becomes smaller. Scraps adhere to the holding line. Therefore,
The film F and the drum 9 do not come into uniform contact with each other, and the film F is lifted up by the linearly adhered debris, which results in poor development and lowers image quality.

In particular, if the area of the heating member (drum 14 in FIG. 13) for adhering the photosensitive heat development material is substantially constant in the direction perpendicular to the direction in which the heating member rotates, as shown in FIG. (Drum 14 in FIG. 13) linearly adheres to the peripheral surface, so that immediately, the film F and the drum 9 are not in uniform contact with each other. Developing failure occurs, and image quality deteriorates.

On the other hand, the above problem can be solved by the following means. First, a rotating heating member, a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member, and the sheet-like photosensitive thermal development material is In an image forming apparatus provided with a heat developing section for heating and thermally developing a photosensitive heat developing material by the heating member while the photosensitive heat developing material is brought into close contact with the surface of the heating member by an opposing member, The photosensitive thermal developing material is brought into close contact with the surface of the heating member so that two opposing sides that are sharper than the sides are lateral to the direction in which the heating member rotates, so that a line is formed on the peripheral surface of the heating member. Adhesion of scum can be suppressed, the photosensitive heat developing material and the heating member are relatively uniformly contacted, and the occurrence of defective development can be suppressed, and a good image can be obtained relatively stably.

In particular, when the area of the heating member to which the photosensitive heat developing material is brought into close contact is substantially constant in a direction perpendicular to the direction in which the heating member rotates, a method of supplying the photosensitive heat developing material to the heating member can be used. It is easy to simplify the temperature control of the heating member, etc., and the photosensitive heat development material and the heating member come into relatively uniform contact, and the occurrence of development defects can be suppressed, and a good image can be obtained relatively stably. Can be

The heating member includes a rotating heating member, and a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member. Between the two opposite sides, the sheet-shaped photosensitive heat developing material is supplied so as to be lateral to the direction around the two opposite sides, which is sharper than the other two opposite sides, and the supplied photosensitive heat development By providing a heat developing section for heating and thermally developing a photosensitive heat developing material by the heating member while the material is brought into close contact with the surface of the heating member by the plurality of guide members, a linear surface is formed on the peripheral surface of the heating member. Adhesion of the glaze can be suppressed, the photosensitive heat developing material and the heating member come into relatively uniform contact, and the occurrence of poor development can be suppressed, and a good image can be obtained relatively stably.

In particular, when the area for supplying the photosensitive thermal developing material between the heating member and the guide member is substantially constant, a method for supplying the photosensitive thermal developing material to the heating member, a method for heating the heating member, It is easy to simplify the temperature control and the like, and the photosensitive heat developing material and the heating member are relatively uniformly in contact with each other, so that the occurrence of development failure can be suppressed, and a good image can be obtained relatively stably.

The heating member includes a rotating heating member, and a guide member provided around the heating member for urging the photosensitive thermal development material onto the surface of the heating member. The heat of heating the photosensitive thermal developing material by the heating member and thermally developing the sheet-like photosensitive thermal developing material cut by the heating member while the photosensitive thermal developing material is brought into close contact with the surface of the heating member by the guide member. In an image forming apparatus including a developing unit, a photosensitive thermal developing material is brought into close contact with the surface of the heating member so as to be lateral to a direction in which two sides cut by a rotary cutter are turned,
Since the two sides cut by the rotary cutter are good cut surfaces, it is possible to prevent linear debris from adhering to the peripheral surface of the heating member, and the photosensitive heat developing material and the heating member are brought into uniform contact, and The occurrence of defects can be suppressed, and a good image can be obtained stably.

In particular, when the area of the heating member to which the photosensitive heat developing material adheres is substantially constant in a direction perpendicular to the direction in which the heating member rotates, a method of supplying the photosensitive heat developing material to the heating member can be used. It is easy to simplify the temperature control of the heating member and the like, and the photosensitive heat developing material and the heating member are in uniform contact, so that the occurrence of poor development can be suppressed, and a good image can be stably obtained.

The heating member includes a rotating heating member, and a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member. The sheet-shaped photosensitive heat developing material cut by the method is disposed between the heating member and one of the plurality of guide members so as to be lateral to a direction around two sides cut by a rotary cutter. Supply photosensitive heat developing material to
A rotary developing unit that heats the photosensitive thermal developing material by the heating member and thermally develops the photosensitive thermal developing material while bringing the supplied photosensitive thermal developing material into close contact with the surface of the heating member by the plurality of guide members; Since the two sides cut by the cutter are good cut surfaces, it is possible to prevent linear debris from adhering to the peripheral surface of the heating member, and the photosensitive heat developing material and the heating member come into uniform contact with each other, resulting in poor development. Can be suppressed, and a good image can be stably obtained.

In particular, the photosensitive thermal development material is supplied to the heating member by providing a substantially constant area between the heating member and one of the plurality of guide members for supplying the photosensitive thermal development material. It is easy to simplify the supply method and the temperature control of the heating member, and the photosensitive heat development material and the heating member are in uniform contact, and the occurrence of development defects can be suppressed, and a good image can be obtained stably. Can be

[0026] The heat developing section heat-develops a photosensitive heat-developable material having two opposing sides cut by a rotary cutter and the other two opposing sides cut by a cutting blade. Thermal development of efficiently produced sheet-shaped photosensitive heat-developable material reduces the total cost of image formation, while uniform contact between the photosensitive heat-developable material and the heating member causes development defects. Can be suppressed,
A good image can be obtained stably.

It is preferable that an exposure unit for exposing the photosensitive thermal development material to light and a transport mechanism for transporting the photosensitive thermal development material exposed in the exposure unit to the development unit be provided. Is preferably a rotating drum, and the guide member is preferably a rotatable roller.

[0028]

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 the image forming apparatus of the present embodiment, and FIG. 2 is a left side view of the image forming apparatus of the present embodiment.

The image forming apparatus 100 includes a feeding unit 110 that feeds the film F, which is a sheet-like heat developing material shown in the embodiment, one by one, an exposure unit 120 that exposes the fed film F, Developing unit 1 for developing exposed film F
30. Hereinafter, the image forming apparatus of the present embodiment will be described with reference to the drawings.

The image forming apparatus of the present embodiment can record images on at least three types of films F of 14 × 17, 14 × 14, and 14 × 11 inches. (Overall Configuration) As shown in FIG. 2, the feeding section 110 is provided with trays T for storing a plurality of stacked films F in two upper and lower stages.

The film F of this embodiment has the above-described structure shown in FIG. 8, and is cut into a sheet by the above-described method shown in FIGS. Therefore, the state of the cut surface of the two opposing sides is different from the state of the cut surface of the other two opposing sides. That is, it has a sharply cut surface R cut by a rotary cutter and a relatively poorly cut surface D cut by a cutting cutter.

Above the front end side of each tray T, a suction unit 11 that moves up and down by sucking the front end of the film F is provided.
1 is provided. In the vicinity of the suction unit 111, the film F supplied by the suction unit 111 is provided.
Is provided in the direction of arrow (1) (horizontal direction). Further, the suction unit 111 can move back and forth, and can transport the film F that has been sucked to the feed roller pair 112. Then, the feed roller pair 11
2 are provided with a plurality of transport roller pairs 141 for transporting the film F fed in 2 in the vertical direction. The film F is transported vertically downward by these transport roller pairs 141 as shown by the arrow (2).

Below the thermal developing device 100, a transport direction changing unit 145 is provided. This transport direction converter 14
5 is a pair of conveying rollers 141 as shown in FIGS.
The film F conveyed vertically downward is conveyed in the horizontal direction as shown by the arrow (3), then the conveyance direction is changed from the arrow (3) to the arrow (4) at a right angle, and then conveyed. Film F transported with its transport direction changed
Is transported upward in the vertical direction as shown by the arrow (5).

Note that up to the transport direction conversion unit 145,
The edge of the sharp cutting plane R was the top in the transport direction,
Since the transport direction is converted to a right angle from the transport direction conversion unit 145, the transport is performed such that the sharp side of the cut surface R is on the side in the transport direction.

As shown in FIG. 1, the transport direction conversion unit 145
A plurality of transport roller pairs 142 for transporting the film F transported from the upper side in the vertical direction as shown by the arrow (6) are provided, and transport the film F in the direction (upward in the vertical direction) from the left side surface of the image forming apparatus 100. I do.

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

A developing unit 130 is provided on the upper part of the image forming apparatus 100. In the vicinity of the drum 14 of the developing unit 130, a pair of conveying rollers 142 is used in the direction of arrow (6) (upward).
A supply roller pair 143 for supplying the film F conveyed to the drum 14 to the drum 14 is provided.

The film F is supplied to the drum 14 at a random timing depending on the situation. In addition, instead of supply at random timing, supply may be performed at a certain timing. As an example of supplying with timing, the supply roller pair 143 stops until the next supply position on the circumference of the drum 14 reaches a predetermined rotation position, and the next supply position on the circumference of the drum 14 You may make it rotate at the time of reaching 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 of the developing unit 130
The drum 14 heats and thermally develops the film F while rotating in the direction indicated by the arrow (7) in FIG. That is, the latent image of the film F is formed into a visible image.

Thereafter, when the film F is rotated to the right with respect to the drum 14 in FIG. A plurality of transport roller pairs 144 are provided on the right side of the developing unit 130, and the film F separated from the drum 14 is
As shown by an arrow (8) in FIG. Then, while the transport roller pair 144 transports the cooled film F, the densitometer 118 reads the film F.
The concentration of is measured. Then, a plurality of transport roller pairs 144
Transports the film F separated from the drum 14 in the horizontal direction as shown by an arrow (9) in FIG.
00 so that the image forming apparatus 100
Is discharged to a discharge tray 160 provided at the upper right side of the printer.

(Feeding Unit) The feeding unit 110 will be described with reference to FIG. 3, which is a configuration diagram of a main part of the feeding unit in FIG.

As shown in FIG. 3, a film F, which is a photosensitive heat developing material having a rectangular shape and substantially the same size and the same shape and rounded at four corners, is substantially aligned on the tray T. A maximum of 126 sheets are deposited. The film F deposited on the tray T is deposited with its photosensitive surface facing down. The suction unit 111 has a suction cup 111a that can be sucked on the front end (one end) of the uppermost film F of the film F deposited on the tray T, and can be moved in the up-down direction and the front-back direction. ing.

Further, the sharp cut surface R of the film F
Are the leading and trailing ends in the transport direction indicated by the arrow H, and the two opposite sides of the dull cut surface D of the film F are lateral to the transport direction indicated by the arrow H. It is deposited to become.

The suction unit 111 is lowered when the image forming apparatus is turned on, and the suction cup 111a is suctioned to one end side of the uppermost film F of the film F deposited on the tray T and reaches a predetermined position. To rise. Next, the suction unit 111 performs a swing motion (reciprocating motion in the vertical direction) several times, sifts off the lifted film F together with the uppermost film F by static electricity or the like, and then enters a standby state.

When the image recording start signal is input, the suction unit 111 moves forward and supplies the film F to the feed roller pair 112. Then, when the feed roller pair 112 starts nipping and transporting the film F, the suction unit 111 releases the suction and moves backward. When the feeding roller pair 112 finishes feeding the film F, the suction unit 111 descends, and the suction cup 111a is suctioned to one end side of the uppermost film F of the film F deposited on the tray T. Then, a standby state is established in the same process as described above.

As described above, when the two opposing sides of the sharp cutting surface R of the film F deposited on the tray T are the leading and trailing ends with respect to the transport direction indicated by the arrow H, the feeding roller It is possible to suppress the generation of debris due to the impact entering the pair 112.

(Exposure Unit) The configuration of the exposure unit 120 will be described with reference to FIG. 4, which is a configuration diagram of the exposure unit in FIG. The exposure unit 120 deflects the laser light L whose intensity has been modulated based on the digital image signal S by the rotating polygon mirror 113,
The main scanning is performed on the film F, and the film F is sub-scanned by relatively moving the film F in a direction substantially perpendicular to the main scanning direction, thereby forming a latent image on the film F.

The image forming apparatus 100 includes a radiation CT apparatus,
The D / A converter 122 converts the digital image signal S transmitted from the image transmission device 121 such as a scanner into an analog signal, and inputs the analog signal to the modulation circuit 123. The modulation circuit 123 controls the laser light source unit 109 via the driver 124 based on the image signal obtained by the analog conversion.

The laser light L emitted from the laser light source unit 109 is converted into parallel light by the condenser lens 108, and is transmitted by the cylindrical lens 115 in one direction (vertical direction in the present embodiment).
Polygon mirror 11 that converges only in
3 is incident as a line image perpendicular to its drive axis.

The rotary polygon mirror 113 reflects and deflects the laser beam L in the main scanning direction, and the deflected laser beam L includes a cylindrical lens formed by combining four lenses.
After passing through the θ lens 114, the film F is reflected by a mirror 116 provided on the optical path extending in the main scanning direction, and is conveyed (sub-scanned) by the conveying device 142 in the arrow Y direction (sub-scanned). Is repeatedly main-scanned in the direction of the arrow X. Thus, the laser light 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.
Converge only in the sub-scanning direction. Thus, the main exposure unit 1
In 20, a cylindrical lens 115 and an fθ lens 114 including a cylindrical lens are provided, and the laser beam L is once converged on the rotary polygon mirror 113 only in the sub-scanning direction. Even if the mirror 113 is tilted or deviated, the scanning position of the laser beam L does not shift in the sub-scanning direction on the surface to be scanned of the film F, so that scanning lines of equal pitch can be formed. It has become. 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.

In the exposing section 120, the sharply cut surface R of the film F is lateral to the conveying direction, and is linearly formed on a pair of conveying rollers 142 before and after the exposing area of the exposing section 120 in the conveying direction. It is possible to suppress the generation of exposure defects due to the adhesion of the residue and the transfer of the accumulated residue onto the surface of the film F.

(Developing Unit) The developing unit 130 for heating the film F will be described with reference to FIGS. More specifically, FIG. 5 is a perspective view of the developing unit 130 as viewed obliquely from behind, and FIG. 6 is a cross-sectional view of the configuration of FIG. 7 is a diagram of the developing unit 130 viewed from the side (the direction of arrow B in FIG. 5).

The developing section 130 has a drum 14 for heating the film F while holding it on the outer peripheral surface. Drum 1
Reference numeral 4 is for forming the latent image formed on the film F as a visible image by maintaining the film F held on the outer periphery at a predetermined minimum heat development temperature or higher for a predetermined heat development time. Here, the minimum thermal development temperature is a minimum temperature at which a latent image formed on the film F starts to be developed by a thermal reaction.
The temperature is around 0 ° C. 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.

In this embodiment, the developing unit 130 is incorporated in the image forming apparatus 100 together with the exposing unit 120, but may be a device independent of the exposing unit 120. In this case, the film F is transferred from the exposure unit 120 to the development unit 130.
It is preferable that there is a transport unit for transporting.

As shown in FIG. 5, outside the drum 14, 20 small-diameter rollers 16 are provided as guide members, and are parallel to the drum 14.
Are arranged at equal intervals in the circumferential direction. Guide brackets 2 supported on a frame 18 are provided at both ends of the drum 14.
3 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. Accordingly, each roller 16 is urged toward the outer peripheral surface of the drum 14 by the combined force of its own weight and the urging force of the coil spring 28. When the film F enters between the outer peripheral surface of the drum 14 and the roller 16, the film F is pressed against the outer peripheral surface of the drum 14 by this urging force,
As a result, the film F is uniformly heated over the entire surface and thermally developed.

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 23a is formed on a rotation shaft 23 of the step motor which is disposed below the shaft 22 and attached to the end member 20.
On the other hand, a gear 22a is also formed on the shaft 22.
The rotation of the step motor is transmitted to the shaft 22 via the gear 23a and a timing belt (belt on which the gear is engraved) 25 around which the gear 22a is wound.
Rotates. The transmission of power from the rotating shaft 23 to the shaft 22 may use a chain or a gear train instead of the timing belt.

As shown in FIG. 6, in this embodiment,
The roller 16 is provided over an angular range of about 171 degrees around the drum 14. Two reinforcing members 3
Reference numeral 0 (FIG. 5) connects both end members 20 of the frame 18 and additionally supports both end members 20.

As shown in FIG. 7, a plate-shaped heater 32 is attached to the inner periphery of the drum 14 over the entire periphery.
Under the control of the control electronic device 34, the outer periphery of the drum 14 is heated. The power supply to the heater 32 is provided by a slip ring connected to the control electronics 34.
This is performed via the assembly 35.

In this embodiment, the image forming apparatus 100
In order to make the structure of the drum 14 compact, the drum 14 is formed in a rotatable cylindrical shape. Alternatively, for example, the film F is placed on a belt conveyor provided with a heater, and the film F is conveyed by the belt conveyor while heating. The configuration may be as follows.

As shown in FIG. 6, the drum 14 includes a support tube 36 made of aluminum, 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, from the viewpoint of reducing the temperature unevenness on the outer periphery of the drum 14, the thickness unevenness of the support tube 36 is preferably kept within, for example, 4%. Furthermore, the flexible layer 3
8 preferably has a sufficiently smooth surface to increase the degree of adhesion to the film F to be heated, and has a surface roughness Ra of preferably 5 μm or less, more preferably 2 μm or less.

When the flexible layer 38 is made of a specific material such as silicon rubber, its surface roughness (R
a) is 0.3 μm in order to prevent the film F from sticking to the drum 14 and to make it easier for gas such as a volatile material to be discharged from between the flexible layer 38 and the film F.
m or more is better.

The flexible layer 38 contains an additive for increasing the thermal conductivity and silicon rubber. The surface roughness (Ra) of the flexible layer 38 is used to prevent the film F from sticking to the drum 14 and to make it easier for gas such as a volatile material to be discharged from between the flexible layer 38 and the film F. In addition, it is better to be 0.3 μm or more. The surface roughness Ra
Is 0.3 μm or more, the gas, especially the volatile material,
It is easy to be 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, whereby the surface temperature of the outer peripheral surface of the drum 14 is maintained uniformly. In this embodiment, the thermal conductivity of the flexible layer 38 is set to 0.4 W / m / K or more.

Since the flexible layer 38 is used, the film 16 can be more firmly adhered to the drum 14 by the roller 16 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 hardness is 55 or less in Shore A hardness measured by a durometer.

The thickness of the soft layer 38 is preferably in the range of 0.1 to 2 mm, and the thinner soft layer 38
Can be used, but there is a problem that the function of the flexible layer 38 decreases as the thickness thereof becomes thinner, and that the manufacturing thereof becomes difficult.

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, 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, suppression of heat conduction is assisted, whereby the influence of 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.

The urging force of the coil spring 28 determines the pressing force of the roller 16 so that the film F can be more closely adhered to the outer peripheral surface of the drum 14 and receive sufficient heat transfer. Care must be taken in the selection. If the urging force of the coil spring 28 is too small, heat may be transmitted unevenly to the film F, and the development of the groove 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, more preferably 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, the roller 1
There is a risk that the drum 6 will not rotate with respect to the drum 14. In particular, if the urging force from the roller 16 per 1 cm width of the film F is 7 g or less, the film F does not rotate. In this case, the film F rotates with the drum 14 and
When the roller 16 is in contact with the film F, the film F
May be damaged by the roller 16. In such a case, it is preferable to provide driven portions on both ends of the rollers 16 and to rotate the rollers 16 by means such as gear driving and friction driving via the driven portions.

Further, 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. Therefore, the urging force from the roller 16 per 1 cm width of the film F is 200 g or less, especially 100 g.
g or less. In the present embodiment, the urging force from the roller 16 per 1 cm width of the film F is 5 g.
７7 g. In addition, a driven portion is provided at both ends of the roller 16, and the roller 16 is driven to rotate by means of gear driving, friction driving, or the like via the driven portion, and the force is maintained within this range. Harmony with the reduction of non-uniformity of the image can be achieved.

The rollers 16 are sufficiently separated from each other in order to suppress uneven expansion due to thermal expansion and contraction of the film F itself, and to prevent the leading edge of the film F from extending tangentially between the rollers 16 due to these and rigidity. Must be close to Such an arrangement is important for holding the film F between the roller 16 and the drum 14. In order to do so, the diameter of the drum 14 is 5 cm to 30 cm,
The distance between the rollers 16 is 1 to 5 cm, and the diameter is 0.5 to 2 c.
m is preferable. This is particularly useful for thermally developing a film having a base thickness of 0.1 to 0.2 mm.

As shown in FIGS. 6 to 8, 20 rollers 1
6 are provided over 171 degrees in the rotation direction of the drum 14, and each space is separated by 9 degrees from the center. In this configuration, the diameter of the drum 14 is 16 cm.
And when 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 relatively hard film such as a polyester film having a base thickness of 0.18 mm, or a base having a thickness of 0.18 mm It is effective for films having a smaller hardness of 0.10 mm such as polyester films.

The heater 32 is mounted on the inner circumference of the drum 14 to heat the outer circumference of the drum 14.
The heater 32 for heating the drum 14 uses an etched resistive foil heater.

The control electronic device 34 rotates together with the drum 14 so that the power supplied to the heater 32 can be adjusted according to the sensed temperature information.
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, it is preferable to maintain the temperature unevenness in the width direction of the drum 14 within 2.0 ° C., particularly preferably within 1.0 ° C. In the present embodiment, the temperature is set within 0.5 ° C. The undeveloped film F supplied at a predetermined timing from the supply roller pair 143 is supplied to the developing unit 130 by the drum 14,
It is supplied to the nip 52 formed by the roller 16 on the most upstream side (see FIG. 6). 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 pressed against the outer periphery of the drum 14 for a predetermined time during the rotation.

In the developing section 130, two opposing sides of the sharply cut surface R of the film F are lateral to the transport direction. The drum 14 moves at substantially the same speed as the film F to be developed, that is, the film F and the drum 1
By moving in a state where there is almost no slip between the film F and the film 4, the possibility that the surface of the film F is scratched (damaged or damaged) is reduced, whereby a high-quality image can be secured. After being transported between the drum 14 and the roller 16, the developed film F is guided by the nip portion 5 formed by the roller 16 and the drum 14 located at the most downstream side, and is pulled out from the developing unit 130. .

The drum 14 is maintained at a temperature of 115 ° C. to 138 ° C., for example, 124 ° C. The drum 14 keeps the film F in contact with its outer peripheral surface for about 15 seconds, which is a heat development time. It is rotated at a rotation speed.

Further, the drum 14 may be a rotating roller, and a cylindrical drum or a supported flat endless belt may function as the roller 16. It is preferable that the surface of the film F on the side having the photosensitive heat developing material (photosensitive surface) is in contact with the outer peripheral surface of the drum 14 (the flexible layer 38 in this embodiment). However, the opposite surface of the film F is the outer peripheral surface of the drum 14 (the flexible layer 38 in the present embodiment).
A configuration in contact with

Following the thermal development of the image, the film F is separated from the surface of the drum 14 of the developing unit 130, guided in a direction away from the surface of the drum 14, and then cooled by the cooling device 15.
It is guided in the direction of 0A. As a result, the possibility that the film F is scratched (damaged) is reduced, and the risk of abrasion of the surface is also reduced. In addition, the cooling device 150A cools the developed film F to a lower part at first, and then cools it rapidly.

According to the image forming apparatus having the above-described structure, in the heat developing section 130, two opposing sides having two sharp cutting planes R cut by the rotary cutter of the film F are arranged in the rotation direction of the drum 14. To be on the side,
By adhering to the surface of the drum 14, the drum 14
Can be prevented from adhering to the peripheral surface of the film F in a circumferential line, the film F and the drum 14 are uniformly contacted, and the occurrence of development failure can be suppressed, and a good image can be stably obtained.

Further, it is possible to suppress the occurrence of exposure defects and development defects due to the adhesion and accumulation of circumferential debris on the roller pairs 142 and 143 and the transfer of the collected debris onto the film F.

[0085]

According to the present invention, the occurrence of defective development can be suppressed, and a good image can be obtained relatively stably.

[Brief description of the drawings]

FIG. 1 is a front view of an image forming apparatus.

FIG. 2 is a left side view of FIG.

FIG. 3 is a configuration diagram of a main part of a feeding unit in FIG. 2;

FIG. 4 is a configuration diagram of an exposure unit in FIG. 1;

FIG. 5 is a perspective view of a developing unit in FIG.

6 is a cross-sectional view taken along the line AA of FIG.

FIG. 7 is a view in the direction of arrow B in FIG. 5;

FIG. 8 is a cross-sectional view of a film used in the embodiment;
FIG. 3 is a diagram schematically showing a chemical reaction in a film at the time of exposure.

FIG. 9 is a cross-sectional view of a film used in the present embodiment,
FIG. 3 is a diagram schematically illustrating a chemical reaction in a film during heating (development).

FIG. 10 is a diagram illustrating a step of slitting a film.

FIG. 11 is a diagram illustrating a process of cutting a film.

FIG. 12 is a diagram illustrating a cut surface of a film.

FIG. 13 is a diagram illustrating a problem.

[Explanation of symbols]

 F Film T Tray D Sharp cutting surface R Sharp cutting surface 14 Drum 16 Roll 120 Exposure unit 130 Developing unit 142 Roller pair 143 Roller pair

Claims (12)

[Claims] And a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member. While bringing the photosensitive thermal development material into close contact with the surface of the heating member by the facing member,
In an image forming apparatus including a heat development unit that heats and develops a photosensitive heat development material by the heating member, the two opposite sides having sharper than the other two opposite sides with respect to a direction in which the heating member rotates. An image forming apparatus, wherein a photosensitive heat developing material is brought into close contact with the surface of the heating member so as to be on the side. 2. The image forming apparatus according to claim 1, wherein a region of the heating member to which the photosensitive heat development material is adhered is substantially constant in a direction perpendicular to a direction in which the heating member rotates. 3. A heating member that rotates, and a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member, wherein the heating member and the guide member are provided. In between, supply a sheet-shaped photosensitive heat developing material so as to be lateral to the direction around the opposing two sides, which is sharper than the other opposing two sides,
An image forming apparatus comprising: a heat developing unit that heats a photosensitive heat developing material by the heating member and thermally develops the photosensitive heat developing material while bringing the supplied photosensitive heat developing material into close contact with the surface of the heating member by the plurality of guide members. 4. The image forming apparatus according to claim 3, wherein an area for supplying the photosensitive thermal developing material between the heating member and the guide member is substantially constant. 5. A heating member that rotates, and a guide member provided around the heating member and for urging the photosensitive thermal development material onto the surface of the heating member, wherein two opposing sides are rotary cutters. The heat of heating the photosensitive thermal developing material by the heating member and thermally developing the sheet-like photosensitive thermal developing material cut by the heating member while the photosensitive thermal developing material is brought into close contact with the surface of the heating member by the guide member. An image forming apparatus having a developing unit, wherein a photosensitive heat developing material is brought into close contact with a surface of the heating member so as to be lateral to a direction in which two sides cut by a rotary cutter are turned. Image forming device. 6. The image forming apparatus according to claim 5, wherein a region of the heating member to which the photosensitive thermal development material is adhered is substantially constant in a direction perpendicular to a direction in which the heating member rotates. 7. A heating member which rotates, and a guide member provided around the heating member and for urging the photosensitive thermal developing material onto the surface of the heating member, two opposite sides of which are rotary cutters The sheet-shaped photosensitive heat developing material cut by the method is disposed between the heating member and one of the plurality of guide members so as to be lateral to a direction around two sides cut by a rotary cutter. The photosensitive heat developing material is supplied to the heating member, and the photosensitive heat developing material is heated by the heating member while the supplied photosensitive heat developing material is brought into close contact with the surface of the heating member by the plurality of guide members. An image forming apparatus, comprising: 8. The image according to claim 7, wherein a region for supplying the photosensitive thermal development material is substantially constant between the heating member and one of the plurality of guide members. Forming equipment. 9. The heat developing section thermally develops a photothermographic material, one of two opposite sides of which is cut by a rotary cutter and the other two opposite sides of which are cut by a cutting blade. The image forming apparatus according to claim 5. 10. An exposure unit for exposing a photothermographic material to light, and a transport mechanism for conveying the photothermographic material exposed in the exposure unit to the development unit. 10. The image forming apparatus according to claim 9. 11. The image forming apparatus according to claim 1, wherein the heating member is a rotating drum. 12. The image forming apparatus according to claim 1, wherein the guide member is a rotatable roller.