JP2620601B2 - Drying control method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a drying control method for drying a photosensitive material after wet processing.

<Conventional Technology> Examples of a photosensitive material processing apparatus that performs wet processing include a silver halide photographic copying machine and an automatic developing machine.

The silver halide photographic copying machine sends a photosensitive material (eg, sheet color paper) supplied from a paper supply unit to an exposure unit to expose the same, and sends the exposed photosensitive material to a processing unit for development, bleaching / fixing. The photosensitive material is dried in a drying section to obtain a copy of the original image.

In addition, the automatic developing machine develops, bleaches, fixes, and processes a photographed photosensitive material (eg, a color negative film) in a processing section.
Washing and stabilization are sequentially performed, and the photosensitive material is dried in a drying unit to obtain a negative image or a positive image.

A drying device provided in a drying section of such a photosensitive material processing apparatus includes a duct surrounding a photosensitive material transport path,
It has a fan and a heater for supplying hot air into the duct, and blows hot air onto the wet photosensitive material conveyed in the duct to dry.

However, in such a conventional drying apparatus, the amount of warm air that actually hits the surface of the photosensitive material and contributes to the removal of moisture, despite the fact that a large amount of warm air is supplied due to the large volume of the internal space of the duct. And the drying time is long.

In particular, in a wet copying machine or an automatic developing machine, a long drying time is a major obstacle in shortening the entire processing time.

In addition, a large amount of air is heated, which consumes a large amount of energy and generates a large amount of exhaust heat, which adversely affects the environment in which the equipment is installed, such as increasing the temperature and humidity. There is also a disadvantage that (preheating) takes time.

Since the preheating time is long, the drying device cannot be turned on and off every time the photosensitive material is processed, and the drying device must be operated regardless of whether the photosensitive material is being processed or not. Therefore, the energy consumption also increased in this respect.

Further, the conventional drying apparatus has the following disadvantages relating to the emulsion layer of the photosensitive material.

In the conventional drying device, about 70 to 95% of the hot air that has been supplied into the duct and contributed to the drying is recovered, and is supplied again into the duct. Therefore, when the photosensitive material is continuously processed, drying is performed with high-humidity warm air, and there is a disadvantage that film quality defects such as reticulation (cracks) occur on the emulsion surface of the photosensitive material.

<Problems to be Solved by the Invention> The object of the present invention is to solve the above-mentioned disadvantages of the prior art,
It is an object of the present invention to provide a drying control method that has good drying efficiency, particularly a short drying time, consumes less energy, and can reduce the size of an apparatus.

Another object of the present invention is to provide a drying control method capable of preventing film quality defects such as reticulation from occurring on the emulsion surface of a photosensitive material.

<Means for Solving the Problems> Such an object is achieved by the present invention described below.

That is, the present invention is a control method for drying a photosensitive material by passing a photosensitive material through the internal space of the housing while supplying a drying gas to the internal space of the housing, Has a slit shape in which the thickness in the thickness direction of the photosensitive material is thin, and the thickness of the internal space is 3 to 1000 times the thickness of the photosensitive material.
The total length of the housing is 30 to 1000 times the total length of the air blowing unit for blowing the drying gas into the internal space of the housing, and the vicinity of the drying end portion in the internal space. This is a drying control method characterized by controlling so that a value obtained by subtracting the relative humidity near the drying start portion from the relative humidity is 30% RH or more.

Further, in the present invention, the drying device is provided with control means for controlling the drying device to operate at the start of drying and to stop the operation at the end of drying.

In these drying devices, it is preferable that the temperature of the drying gas supplied to the photosensitive material emulsion side of the internal space of the housing is 70 ° C. or higher.

Further, it is preferable that the drying apparatus has a dehumidifying means for removing moisture from the drying gas.

In the same technical field as the present invention,
There is a drying apparatus for photographic processing disclosed in 44331.

This photographic processing drying device is, `` In a device that performs hot air drying between the photosensitive material feed roller and the feed roller, the drying air that has become hot air flows on the surface of the photosensitive material inside the hot air drying device and is dried, A drying device for photographic processing, characterized in that a discharging device for discharging the drying air containing moisture after completion of the drying step from a part of the hot-air drying device is provided. "

However, this drying apparatus for photographic processing is intended for short-time drying and automatic conveyance of the photosensitive material in a conveyance path (corresponding to the slit-shaped internal space of the present invention) by an air flow.
It does not focus on the difference in humidity between the drying start part and the drying end part as in the present invention.

In particular, the overall length of the transport passage of this photographic processing drying apparatus is short, and is only about two to three times the total length of the nozzle blowing section. Further, there is no means for dehumidifying the supplied air.

Therefore, in this photographic processing drying apparatus, the difference between the relative humidity near the drying start portion and the relative humidity near the drying end portion in the transport path cannot be set to 30% RH or more.
Reticulation of the emulsion surface of the photosensitive material cannot be prevented.

<Operation> In the present invention having such a configuration, the internal space of the housing through which the photosensitive material passes is made into a slit shape having a thin thickness in the thickness direction of the photosensitive material, thereby significantly reducing the volume thereof. A small amount of drying gas can be flowed at a high speed, and as a result, drying can be performed in a short transport path in a short time, energy can be saved, adverse effects on the indoor environment can be prevented, and the apparatus can be downsized.

The difference between the relative humidity near the drying start portion and the relative humidity near the drying end portion in the internal space of the housing is 30% RH.
As described above, film quality defects such as reticulation do not occur on the emulsion surface of the photosensitive material.

In addition, even when drying with hot air, the amount of the drying gas to be heated is small, so that preheating can be instantaneously performed.
It is possible to perform control such that air blowing is started immediately before the start of drying, and air blowing is stopped after drying is completed. As a result, air is blown only during drying, which can further reduce energy consumption and prevent adverse effects on the indoor environment in which the device is installed.

<Embodiment> Hereinafter, a preferred embodiment of the drying apparatus of the present invention shown in the accompanying drawings will be described in detail.

1 to 8 are longitudinal sectional views each showing a configuration example of a drying apparatus used in the present invention. In the drawings, the same members are denoted by the same reference numerals, and the description of the same items is omitted.

As shown in FIG. 1, a drying apparatus 1a used in the present invention comprises:
The housing 2 has a rectangular box-like cross section. An entrance 4 for the photosensitive material S is formed at the left end of the casing 2 in the figure, and an exit 5 for the photosensitive material S is formed at the right end in the figure. ing. In this specification, the inlet 4 side is described as “front”, and the outlet 5 side is described as “rear”.

An inner space 3 penetrating from the inlet 4 to the outlet 5 is formed in the housing 2, and the inner space 3
Has a thin slit shape in the thickness direction (vertical direction in the figure). That is, the cross section of the internal space 3 has a slit shape. The dimensions of the internal space 3 will be described later in detail. In the illustrated example, the internal space 3 has a flat shape. However, in the present invention, the internal space 3 may have an appropriately curved shape as long as the passage of the photosensitive material S is not hindered.

A vicinity of the inlet 4 of the housing 2, on the surface of the photosensitive material S (emulsion surface) S _A side and the back surface S _B side (in the drawing upper and lower), a pair of nozzles 8 communicating with the internal space 3, respectively Is installed.

A slit-shaped outlet is formed at the tip of each of the nozzles 8, and the outlet 7 of a fan (blower) 6 is connected to the base of the nozzle 8.

In addition, the nozzle 8 is installed with its tip inclined toward the rear, and the drying gas (air or other inert gas sent out from the exhaust port 7 by the operation of the fan 6; (Represented by air) is ejected from the tip of the nozzle 8 into the internal space 3 and forms a high-speed flow backward in the internal space 3 of the housing. The air that has passed through the internal space 3 is discharged from the outlet 5.

In this way, the wet photosensitive material S nipped and transported by the pair of transport rollers 30 is introduced into the inlet 4 while passing the air at a high speed from the front to the rear in the internal space 3, and passes through the internal space 3. If is, water is removed from the surface S _a and the back surface S _B of the photosensitive material S, is dried.

In this case, the humidity of the atmosphere in the internal space 3 gradually increases from the front to the rear.

That is, in the present invention, the value obtained by subtracting the relative humidity near the drying start portion X from the relative humidity near the drying end portion Y is 30% RH or more,
Preferably, it is about 50 to 90% RH.

Thus, the film quality defects of the surface (emulsion surface) S _A of the photosensitive material S, in particular reticulation is prevented.

In the configuration example shown in FIG. 1, the position of the drying start portion X is near the air blowing port of the nozzle 8, and the position of the drying end portion Y is near the outlet 5 of the housing 2. The second described later
When a plurality of pairs of nozzles are installed along the longitudinal direction of the housing as in the configuration example shown in FIG. 7 and FIG. 7, the position of the drying start part X is near the air inlet of the foremost nozzle. And

Note that the inlet 4, to facilitate introduction of the photosensitive material S, on the surface S _A side and the back surface S _B side of the photosensitive material, the inclined surface inclined rearward is formed, also, the inclined surfaces 4a At the tip of the air, the air ejected from the nozzle 8 flows backward,
A barb (step portion) is formed to suppress exit from the inlet 4.

Further, it is preferable that the inclination angle α of the nozzle 8 be about 5 ° to 60 °. If α is less than 5 °, the size of the housing 2 becomes large, which makes it difficult to design compactly.
Is more than 60 °, backflow to the inlet 4 is likely to occur.

In this configuration example, by supplying air from each of the surface side and the back side of the photosensitive material S, and between the rear surface S _B and the housing of the surface S _A and housing wall 2a of passing the photosensitive material S to the inner space 3 An airflow is formed between the photosensitive material S and the wall 2b, so that the photosensitive material S can be prevented from closely contacting the inner walls 2a and 2b of the housing. In consideration of the prevention of the close contact of the photosensitive material S, the shape and the installation angle α of the nozzles 8 provided on the front surface side and the back surface side of the photosensitive material S are symmetrical to maintain the balance of the air flow. Preferably, the supply amounts are also equal.

FIG. 9 is a sectional view taken along line IX-IX in FIG. As shown in the drawing, and the width W _N of the air outlet of the nozzle 8, the width W _S of the photosensitive material S, preferably a W _N <W _S the relationship.

Thus, the air jetted from above and below each nozzle 8 hits the surface S _A and the back surface S _B of the photosensitive material S, as indicated by the arrow, so is diverted in the direction of both end portions of the photosensitive material S The balance of the air flow between the photosensitive material S and the housing inner wall 2a side and the housing inner wall 2b side is maintained, so that the vertical and horizontal swinging of the photosensitive material S in the drawing is suppressed, and the stabilization is achieved. I can do it.

Although not shown in the drawings, as means for preventing the photosensitive material from adhering, as shown in Japanese Patent Application No. 62-277678, for example, a flexible member projecting inward (for example,
Loop-shaped fiber), or a protrusion, groove or other guide member extending in the longitudinal direction of the housing is provided on the housing inner walls 2a and 2b as means for preventing the photosensitive material from swinging. It is possible.

The transport of the photosensitive material S in the housing 2 is performed as follows.

If the length of the photosensitive material S is longer than the length of the housing 2 (more precisely, the distance between the entrance-side transport roller 30 and the exit-side transport roller 31), the rotational force of the transport rollers 30 and 31 It is performed by

That is, before the rear end (front end) of the photosensitive material S comes off the transport roller 30, the front end (rear end) of the photosensitive material S is nipped by the transport roller 31.
Is transported by nipping the internal space 3 of the housing by at least one of the transport rollers 30 and 31.

If the length of the photosensitive material S is shorter than the length of the housing 2, the photosensitive material S is separated from the conveying roller 30, and then is moved behind the high-speed airflow flowing through the internal space 3. (Hereinafter referred to as air transport), and after the leading end of the photosensitive material S reaches the transport roller 31, the photosensitive material S is nipped and transported by the roller 31. Note that, even in this case, the internal space 3
A driving roller pair or a circulating endless belt such as a roller conveying system or a belt conveying system may be provided.

The width of the internal space 3 of the housing 2 is larger than the width W _S (maximum) of the photosensitive material S, and the thickness T of the internal space 3 is 3 to 1000 times the thickness of the photosensitive material S. And especially 5
It is preferably about 100 times.

If the thickness is less than three times the thickness of the photosensitive material S, troubles such as adhesion failure and scratches on the photosensitive material S are likely to occur during drying,
In addition, when it exceeds 1000 times, the volume of the internal space 3 becomes large,
This is because the effects of the present invention may not be sufficiently exhibited depending on the drying conditions.

The thickness T of the internal space 3 may gradually increase or decrease from the front to the rear, that is, the internal space 3 may be tapered.

Thereby, the flow velocity of the air in the longitudinal direction of the internal space 3 can be changed. For example, when the flow rate of air in the first half of the drying is large (T gradually increases toward the rear), the second half of the drying is gradually dried, and especially in a light-sensitive material having a small hardener and a light-sensitive material having a thick emulsion layer. On the other hand, there is an effect of preventing film quality deterioration. In the opposite case (T gradually decreases toward the rear), the drying tends to be slightly rapid even in the latter half of the drying, and the drying pass (time) is particularly short for photosensitive materials having a thin emulsion layer, which is preferable.

The drying device 1b shown in FIG. 2 has a configuration in which a plurality of nozzles are provided along the longitudinal direction of the housing 2. As shown in the figure, nozzles 8, 8 ′ and 8 ″ are installed on the upper and lower sides of the housing 2 in order from the front to the rear, respectively, and a branch duct 9 branched from near the exhaust port 7 of the fan 6 is provided. It is connected to the proximal end of the nozzles 8 'and 8 ".

The nozzles 8 'and 8 "are similar to the nozzle 8 described above.

For the same reason as described above, it is preferable that the shapes, installation angles, arrangements, and the like of the nozzles are symmetrical on the front surface side and the back surface side of the photosensitive material S, and that the total amount of supplied air is also equal.

As described above, when a plurality of pairs of nozzles are provided, when the air flow ejected from the nozzle 8 is attenuated due to the pressure loss, new air is ejected by the nozzle 8 'and further by the nozzle 8 "behind the nozzle 8'. By doing so, this can be recovered.

Therefore, it is advantageous to apply such a configuration when the length of the housing 2 is relatively long, when the photosensitive material S is conveyed by air, and when the drying efficiency is increased.

In the drying device 1b, the total length of the housing 2 is at least 30 times the total length of the air blowing portions of the nozzles 8, 8 ', 8 ",
More preferably, it is 100 to 1000 times. Thereby, the above-mentioned humidity difference between the drying start portion X and the drying end portion Y can be easily achieved.

The drying devices 1c and 1d shown in FIGS. 3 and 4 have heating means for heating the drying air, and dry the photosensitive material S with warm air. Thereby, the drying device
Drying efficiency is improved as compared with 1a and 1b.

The drying device 1c is provided with a heater 10 in an exhaust port 7 of a fan 6 and jets the air heated by the heater 10 from a nozzle 8 into the internal space 3 of the housing 2 (first). 3
See figure).

Temperature of hot air supplied to the interior space 3 is not particularly limited, for example, 40 to 150 may also be, but on the order ° C., at least the temperature of the warm air is supplied to the surface S _A side of the photosensitive material S is 70 ° C.
It is preferable that this is the case.

The difference T _max -T _min between the maximum temperature T _max and the minimum temperature T _min of the atmosphere in the interior space 3 is preferably about 20 to 100 ° C.. This is because such a temperature difference (particularly 40 ° C. or more) reliably prevents reticulation of the emulsion surface.

The drying device 1d includes a panel heater (a sheet heating element) 11 on the outer wall on the front side and the back side of the photosensitive material S of the housing 2, respectively.
When the air blown from the nozzle 8 passes through the internal space 3 where the panel heater 11 is installed, the housing receives heat from the inner wall of the housing and is heated. (See FIG. 4). The same applies to the temperature in this case.

From the viewpoint of improving the drying efficiency and the film quality of the emulsion layer of the photosensitive material S, the panel heater 11 is preferably installed at least in the first half of the drying, that is, in the front side of the housing 2.

In such a drying apparatus 1c and 1d, the surface S _A side and the back surface S _B side of the drying temperature of the photosensitive material S (temperature of the drying air) may be equal, but the drying temperature of the surface S _A side Back
Preferably higher than the drying temperature of the S _B side.

Specifically, the drying temperature of the rear surface S _B side is less than 70 ° C. 40 ° C. or higher, and the like if the drying temperature of the surface S _A side and 70 ° C. or higher 0.99 ° C. or less.

Table such photosensitive material, for reasons of providing a difference in drying temperature back to the first, naturally, possible to dry the surface S _A of the light-sensitive material with the emulsion layer preferentially to the second, the light-sensitive material The purpose is to prevent curling and improve transportability in the housing 2.

It should be noted that providing a preferable value of the drying temperature and providing a difference in the drying temperature is the same in each configuration example described later.

The drying devices 1e and 1f shown in FIGS. 5 and 6 have dehumidifying means for removing moisture from the drying air and heating means for heating the drying air, and circulate the air after drying. It is to be reused.

By providing such a dehumidifying means, it is possible to easily achieve the above-described humidity difference between the drying start portion X and the drying end portion Y.

The drying device 1e shown in FIG. 5 has an air circulation system having a symmetrical structure on the front side and the back side of the photosensitive material of the housing 2, respectively. This air circulation system has a duct 12, and a recovery port 13, which is a rear end of the duct 12, is provided near the outlet 5 of the housing 2. Further, a slit-shaped opening 121 through which the photosensitive material S passes is formed at a side portion thereof. The opening 121 has a convergent shape so that the photosensitive material S can easily pass therethrough and air leakage is small.

A dehumidifier 14 is installed in the middle of the duct 12, and a propeller fan 15 is installed in a portion where the internal space of the duct 12 is enlarged in front of the dehumidifier. Further, a heater 16 is installed in the duct 12 in front of the fan 15,
The front end of 12 is connected to the base end of the nozzle 8.

The dehumidifier 14 is, for example, one using a normal refrigerant such as an air conditioner, one using an electronic cooling element utilizing the Peltier effect (Japanese Patent Application No. 63-221796), or a desiccant such as calcium chloride or silica gel. Various structures can be used, such as a simple structure in which a (hygroscopic agent) is placed and air containing moisture passes therethrough. Among them, the configuration of the dehumidifier using the electronic cooling element will be representatively described.

As shown in FIG. 10, the dehumidifier 14 has a hollow main body 40, in which a Peltier element (electronic cooling element) 41 utilizing the Peltier effect is installed.

The Peltier element is arranged such that the right side in FIG. 10 is the heat absorbing section 42 and the left side is the heat radiating section 43.

An opening 44 is formed on the heat absorbing portion 42 side of the main body 40 at a position facing the Peltier element 41, while a heat radiating portion of the main body 40 is formed.
On the 43 side, an opening 45 is formed at a position facing the Peltier element 41. These openings 44 and 45 accommodate the duct 12
Is connected.

At the lower end of the Peltier element 41 on the heat absorbing section 42 side,
A drain pipe 47 having 46 is provided, and water droplets generated by dew condensation in the heat absorbing section 42 are discharged out of the main body 40 through the tray 46 and the drain pipe 47 and stored in the tank 48.

In the dehumidifier 14 having such a configuration, as shown by arrows in FIG. 10, air containing much moisture flows into the heat absorbing portion 42 in the main body 40 from the opening 44 by the action of the fan 15, and the Peltier device 41 And diverges in the vertical direction in the figure.

This air is cooled when passing through the heat absorbing section 42, and dew condensation occurs on the surface of the Peltier element 41.

Water droplets generated by the condensation flow down by their own weight, and are stored in a tank 48 via a receiving tray 46 and a drain pipe 47.

The air cooled and dehumidified by the heat absorbing section 42 is guided to the heat radiating section 43 through the upper and lower curved portions of the main body, where it is heated again.

Dry air heated by the heat radiating section 43 passes through the opening 45 to the main body 40.
It is discharged outside. The humidity of the discharged air is, for example, 5 to 20% RH.

The tank 48 may be provided independently for each dehumidifier, or may be common to each dehumidifier.

A dehumidifier using such an electronic cooling element is preferable because it is small in size, has a high dehumidifying capacity, and consumes little power.

In such a drying apparatus 1e, the circulation of air is performed as follows. When the fan 15 is operated, the inside of the collecting port 13 becomes negative pressure, and the air containing much moisture after drying discharged from the outlet 5 is sucked into the collecting ports 13 on the upper and lower sides of the housing 2 and passes through the duct 12. Then, it reaches the dehumidifier 14. This air is dehumidified by a dehumidifier 14, then passes through a fan 15, is preferably heated to about 70 to 150 ° C. by a heater 16, and is ejected again from the nozzle 8 into the internal space 3 of the housing 2.
Form a high-speed flow.

The drying device 1f shown in FIG. 6 is different from the drying device 1e in that
The configuration of the dehumidifying means is different.

That is, openings 17 are formed on the front side and the back side of the photosensitive material on the rear side (the latter half of drying) of the housing 2, respectively. Is mounted. As a specific example of the water vapor permeable member 18, for example,
Fine-meshed nets made of fine metal wires or heat-resistant fibers (eg, glass fiber, carbon fiber, etc.), woven fabric, non-woven fabric, asbestos, porous materials made of heat-resistant resin, unfired plates, foamed ceramics, or other heat-resistant porous materials Quality material. Also, the temperature of the passing air is low (especially 60 ° C
In the case of the following), since heat resistance is not required, in addition to the above, a water vapor selectively permeable cloth (trade name: Gore-Tex),
Porous plastic (for example, Gross Rock "Polex"; material / Ultra-high-molecular-weight polyethylene, polypropylene, polyvinylidene fluoride, etc.), microporous film (for example, Sekisui Chemical Co., Ltd. "Cellpore"; Material / polyolefin-based plastic S) can also be used.

In such a drying device 1f, the circulation of air is performed as follows. The air ejected from the nozzle 8 removes moisture from both surfaces of the photosensitive material S, and the humidity increases as going backward. When the humid air passes through the internal space 3 where the water vapor permeable member 18 is present, water vapor in the air or water vapor and a part of the air pass through the water vapor permeable member 18 and are discharged to the outside of the housing 2. Is done.

As a result, the humidity in the air gradually decreases toward the rear, and low-humidity air is discharged from the outlet 5. The low humidity air is then removed from the upper and lower
Each of them is sucked by 13, passes through a duct 15, passes through a fan 15, is heated by a heater 16 to the same temperature as above, and is ejected again from the nozzle 8 into the internal space 3 of the housing 2 to form a high-speed flow.

In this case, the drying end portion Y is located at the front end or the front half of the water vapor permeable member 18.

Note that the water vapor permeable member 18 may be provided at an intermediate portion of the duct 12 (for example, a portion indicated by a symbol A in FIG. 6). In this case, the drying end portion Y is in the vicinity of the collection port 13 and a gradient is formed in which the humidity gradually increases over the entire length of the housing 2. Therefore, the drying start portion X and the drying end portion Y described above.
And the difference in humidity becomes easier to obtain.

In the drying apparatuses 1e and 1f, the degree of dehumidification may be different between the front side and the back side of the photosensitive material S.
In this case, it is preferable to supply air of lower humidity to the emulsion surface side of the photosensitive material S.

When the drying apparatuses 1a to 1f described above are categorized, the drying apparatuses 1a and 1b are of a cold air supply open type that supplies unheated room-temperature air without circulating, and the drying apparatuses 1c and 1d are configured to supply heated air. The open-air hot-air supply type that supplies without circulation and the drying devices 1e and 1f are of a dehumidified hot-air supply circulation type in which dehumidified and heated air is circulated and supplied.

In the present invention, other than the above ~, for example,
Needless to say, a drying device such as a dehumidified cool air supply open type, a dehumidified hot air supply open type, a cool air supply circulation type, a hot air supply circulation type, a dehumidification cold air supply circulation type, or a combination thereof may be used.

The drying apparatus 1g shown in FIG. 7 performs different forms of drying in the first half and the second half of drying.

The drying device 1g is located on the left side of the housing 2 in FIG. 7 (first half of drying).
Has a symmetric air circulation system on the front and back sides of the photosensitive material.

This air circulation system has a duct 50, the rear end of which
It is connected to the middle of the housing 2 via a collection port 51.

The dehumidifier 19 is installed in the middle of the duct 50, and further in front of the dehumidifier 19, the same fan 6 as described above is installed. Further, an exhaust port 7 of the fan 6 is connected to a base end of a nozzle 8, and a tip of the nozzle 8 is installed so as to communicate with the inside of the housing 2.

Further, a heater 10 is provided in the exhaust port 7 of the fan 6.

The dehumidifier 19 is the same as the dehumidifier 14 described above, and it is particularly preferable to use a dehumidifier using an electronic cooling element shown in FIG.

A pair of transfer rollers 32 for relay are installed in the casing 2 near the collection port 51 of the duct 50.

On the other hand, a pair of nozzles 8 similar to the above are installed on the front side and the back side of the photosensitive material on the right side (the latter half of drying) in FIG. The fan 6 is connected via the.

A heater 10 'is provided in the exhaust port 7 of the fan 6.

In such a drying apparatus 1g, in the first half of the drying operation, the internal space 3 of the housing 2 and the duct 50 are operated by the operation of the fan 6.
Air circulates inside. That is, the air supplied for drying is
It is introduced into the duct 50 from the recovery port 51, and is dehumidified by the dehumidifier 19 in the middle of the duct 50.
It is heated as described above and supplied again from the nozzle 8 to the drying start part X.

Therefore, in the first half of drying, drying is performed by air having a relatively high temperature and low humidity (for example, an average humidity of about 1 to 20% RH).

On the other hand, in the latter half of the drying, the air taken in from the outside by the operation of the fan 6 is heated by the heater 10 ',
The air is supplied from the nozzle 8 to the internal space 3, flows backward in the internal space 3, and is exhausted from the outlet 5. Here, it is preferable that the temperature of the air heated by the heater 10 ′ is lower than that of the heater 10. That is, the calorific value of the heater 10 'is made lower than the calorific value of the heater 10, or the heater 10' is turned off (cool air supply).

Due to this, in the latter half of the drying, relatively low temperature (normal temperature ~ 60 ℃
Degree) and high or medium humidity (for example, average humidity 40 to 90)
% RH).

Thus, in the first half of drying, high temperature and low humidity, and in the second half of drying, low temperature and high humidity (drying in
This is most preferable for preventing reticulation of the emulsion surface of the light-sensitive material.

In the drying device used in the present invention, the constituent material of the housing 2 is not particularly limited, but in the case of the hot air supply type as described above, it is a material having heat resistance,
Preferably, a material having heat insulation properties is used. As a specific example, the casing 2 is made of various ceramics such as alumina, zirconia, asbestos, glass wool, stainless steel,
A case is made of a metal such as Hastelloy, copper, or a copper-based alloy, or a heat insulating material such as asbestos, felt, aluminum foil, or glass wool is bonded to the outer wall of the metal housing.

A panel heater in the drying device 1d shown in FIG.
It is preferable that the housing of the joint portion 11 is made of a material having good thermal conductivity (for example, metal such as copper or a copper-based alloy).

Internal space 3 of housing 2 in the drying device used in the present invention
Table 1 below shows a preferable range of the average flow velocity (linear velocity) of the air for each configuration example.

In addition, the lowest stage in Table 1 shows the average flow velocity of the air in the duct in the conventional drying device.

The average flow velocity of air in Table 1 is calculated from the following equation.

U = V / SU: average flow velocity of air V: air supply amount (flow rate) S: cross sectional area of internal space 3 In the case where air is conveyed in the drying apparatuses 1a to 1h, the average flow velocity in Table 1 is preferably increased by 0 to 20%.

In the drying device used in the present invention, since the internal space of the housing is in the form of a slit having a small thickness, the volume is significantly reduced as compared with the conventional device. This allows a small amount of air to flow at high speed (see Table 1) into the internal space of the housing.

When the photosensitive material S passes through the air flowing at a high speed, the amount of air colliding with the photosensitive material surface per unit time is increased, so that the drying can be performed in a shorter time than before, and the drying devices 1a, 1b Thus, the photosensitive material S can be dried even if it is a cold air supply type.

Further, since the amount of air used for drying is a small amount, as in the case of the drying device 1c to 1g, even when heating the air, the energy consumption for heating is small, and the preheating time at the start of drying is short. . Furthermore, drying equipment 1c, 1d, 1g (the latter half)
As described above, even with the hot air supply open type, the amount of exhaust to the outside and the amount of heat exhausted are small, so that it does not adversely affect the environment in the room where the device is installed (hereinafter referred to as the indoor environment) (temperature rise, etc.).

In the case of a circulation type such as the drying devices 1e, 1f, and 1g (first half), the heat of the air after drying is reused, so that further reduction in energy consumption can be achieved, and exhaust to the outside. Since there is almost no exhaust heat, there is no problem of adverse effects on the indoor environment.

Further, when the dehumidifying means is provided, the drying efficiency is greatly improved. In particular, when a dehumidifying unit and a heating unit are provided, drying is performed with high-temperature and low-humidity air at least at the initial stage of drying, so that film quality defects such as reticulation (cracking) or poor gloss on the emulsion surface of the photosensitive material are caused. Can be prevented.

The drying apparatus 1h shown in FIG. 8 is an example of a configuration provided with control means for controlling the operation and stop of the drying apparatus in accordance with the passage and non-passage of the photosensitive material S in the housing 2. The configuration of this control means will be described below.

In the vicinity of the entrance 4 in front of the housing 2, a sensor 20 capable of detecting the presence of the photosensitive material S is provided.
For example, it is connected to a control unit 21 composed of a microcomputer or the like. The control unit 21 includes a power supply 22 of the dehumidifier 14 on the front side and the back side of the photosensitive material S, a fan,
The power supply 23 is connected to the power supply 23 and the power supply 24 to the heater 16.

Note that the sensor 20 may be of any type such as a touch sensor or an optical sensor.

When the tip of the photosensitive material S passes through the portion of the sensor 20, the presence of the photosensitive material S is detected by the sensor 20, and the detection signal is digitized and input to the control unit 21. Control unit 21
In, based on this input signal, a command signal for turning on each of the power supplies 22, 23 and 24 is output. As a result, the dehumidifier 14, the fan 15 and the heater 16 operate almost simultaneously, and drying starts.

The control unit 21 has a built-in timer,
After a lapse of a certain time (hereinafter referred to as an operation time) from the time when the power supply is turned on, a command signal for turning off each of the power supplies 22, 23, and 24 is output. The operating time is determined by the photosensitive material S
Until the drying of the photosensitive material S is completed, that is, the time until the rear end of the photosensitive material S passes through the outlet 5 or a slightly longer time, and taking into consideration various conditions such as the length of the photosensitive material S and the transport speed, for example, The longest one can be set in advance, or can be set manually or automatically each time according to the above conditions.

Here, in the latter case, the operation time according to the various conditions may be tabulated and stored in the control unit 21, and an optimum value may be selected.

The timing for turning off each of the power supplies 22, 23 and 24 is not limited to the above-described timer, but may be, for example,
A sensor (not shown) similar to that described above is provided at a predetermined position behind the exit side of the photosensitive material S, and the sensor detects that the passage of the photosensitive material S through the housing 2 has been completed. Alternatively, the control unit 21 may be configured to output a command signal for turning off the power supplies 22, 23, and 24 and execute the command signal.

Further, in the present invention, the configuration of the control means is not limited to that for detecting the presence of the photosensitive material S. For example, the rotation of the transport rollers 30 and 31 is mechanically or electrically detected, The power supply 22 may be turned on and off by the power supply 21.

Further, the operation and stop of the drying device are not limited to the automatic control as in each of the above examples. Each of the power supplies 22 to 24 is turned on when starting the drying of the photosensitive material S, and each of the power supplies 22 to 24 is completed when the drying is completed. It may be based on manual control of turning off.

In such control, the O of each of the power supplies 22, 23 and 24 is
N and OFF are not limited to being performed all at the same time, and a time difference may be provided between them.

For example, if the dehumidifier 14 and the heater 16 are stopped and the fan 15 is controlled to stop after a predetermined time, the duct 12
It is possible to prevent partial retention of moisture and heating in the inside, which is preferable. Further, the fan 15 may be operated at all times, and the dehumidifier 14 and the heater 16 may be ON / OFF controlled in the same manner as described above.

According to the drying apparatus 1h having such a control means, since the apparatus is operated only when the photosensitive material S is dried, energy consumption is significantly reduced, and there is no influence on the indoor environment.

The reason why such control has become possible is as follows. In a conventional drying device, since the volume of the duct through which the photosensitive material passes is large, a large amount of air must be heated, and therefore, a long time is required for preheating. Could not be started and stopped.

On the other hand, in the drying apparatus used in the present invention, since the cold air drying is possible as described above, it is not necessary to consider the preheating time, or even in the case of hot air drying, the amount of air to be heated is small. Since the preheating time is extremely short, the drying device can be started and stopped every time the photosensitive material is dried.

The type of the photosensitive material S to be dried in the present invention is not particularly limited. For example, a color negative film, a color reversal film, a color photographic paper, a color positive film, a color reversal photographic paper, a photographic photosensitive material for plate making, an X-ray photographic photosensitive material, Various photosensitive materials such as black-and-white negative films, black-and-white photographic papers, and photosensitive materials for micros are included.

In addition, the drying device used in the present invention is used alone,
Alternatively, automatic developing machines, wet color copiers (AP
C), it can be used in a state of being incorporated in various photosensitive material processing devices such as a video printer processor and a color paper processing machine for plate inspection.

As described above, the configuration of the present invention has been described with reference to some configuration examples.However, the present invention is not limited to these, and for example, a combination of any one of the drying devices 1a to 1h, or Other configurations may be used.

Further, the drying apparatus 1a~1h are all photosensitive material surface S _A side and the back surface S _B side independent air supply system S (fans, ducts, heater, dehumidifier) has the,
However, the present invention is not limited to this, and a configuration may be adopted in which a single air supply system is provided, and air is supplied from this air supply system to the nozzles 8 on the front surface side and the back surface side of the photosensitive material.

<Experimental Example> Hereinafter, a specific experimental example of the present invention will be described.

(Invention Example 1) A drying apparatus having a structure shown in FIG. 2 was manufactured, and the photosensitive material after the wet processing was dried using the drying apparatus. The conditions are as follows.

Housing / Overall length: 1200mm Internal space width: 100mm Internal space thickness T: 4mm Material: Stainless steel Nozzle / Arrangement: 3 pairs, vertical symmetry Tilt angle α: 30 ° (same for each nozzle) Outlet width W _N : 80mm (each) Total nozzle length: 3 mm (1 mm x 3) Drying gas / Supply air temperature: Normal temperature (approx. 24 ° C) Supply air humidity: Normal humidity (approx. 55% RH) Flow rate inside the housing: 12 m / s Photosensitive material / Type: Color paper type 03 manufactured by Fuji Photo Film Co., Ltd. Dimensions: width 89 mm x length 20 m x thickness 220 µm Photosensitive material transport speed / 1.0 m / min (Example 2 of the present invention) A drying device having the structure shown in Fig. 3 was manufactured. Using this, the photosensitive material after the wet processing was dried. The conditions are as follows.

Enclosure / Overall length: 500mm Internal space width: 220mm Internal space thickness T: 3mm Material: Asbestos material Nozzle / Arrangement: 1 pair, vertical symmetry Tilt angle α: 45 ° Outlet width W _N : 190mm Outlet length: 1mm Dry Gas for use / Supply air temperature: 80 ° C Supply air humidity: Normal humidity (55% RH at 24 ° C) Flow rate in the housing: 23 m / s Photosensitive material / Same as Example 1 of the present invention except that width 203 mm was used. 0.5 m / min (Example 3 of the present invention) A drying apparatus having the structure shown in FIG. 7 was manufactured, and the photosensitive material after the wet processing was dried using the drying apparatus. The conditions are as follows.

Enclosure / Overall length: 600mm Internal space width: 43mm Internal space thickness T: 5mm Material: Stainless steel Nozzle / Arrangement: 2 pairs, vertical symmetry Tilt angle α: 30 ° (same for each nozzle) Outlet width W _N : 25mm (each) Nozzle) Total outlet length: 2mm (1mm x 2) Dehumidifier / Structure: Structure shown in Fig. 10 Peltier device: NSELECOOL.Model TECF-40. 40W (34KCal / hour) DC 4A 24V Capacity: 1.1 / 10 hours Drying gas (first half of drying) / Supply air temperature: 70 ° C Supply air humidity: 2% RH or less (70 ° C) Flow rate in housing: 20m / s Drying gas (second half of drying) / Supply air Temperature: 45 ° C. Supply air humidity: 60% RH (normal temperature), 32% RH (45 ° C.) Flow rate in the housing: 13 m / s Same as in Example 1 of the present invention except that the photosensitive material / width was 35 mm. m / min (Comparative Example 1) The total length of the housing is 300 mm, and the internal space thickness T is 40 mm (flow rate 1.2
m / s), the photosensitive material was dried under the same conditions, using the same drying apparatus as in Example 1 of the present invention, except that the nozzle outlet total length was 30 mm and the photosensitive material conveying speed was 0.25 m / min.

(Comparative Example 2) The total length of the housing is 200 mm, and the thickness T of the internal space is 60 mm (flow velocity 1.1
m / s), the total length of the nozzle outlets was 10 mm, the photosensitive material conveying speed was 0.2 m / min, and the supply air temperature was 60 ° C. To dry the photosensitive material.

For each of Examples 1 to 3 of the present invention and Comparative Examples 1 and 2, 40 m of each photosensitive material was continuously dried, and the relative humidity in the drying start section X and the drying end section Y was measured. The results are shown in Table 2 below.

The measurement of humidity is performed by a precision digital thermo-hygrometer (TR
H-10A, sensor THP-12).

In addition, the emulsion surface was observed with a loupe at 10 locations, 1 m, 3 m, and 10 m from the end of the dried photosensitive material, and the occurrence of reticulation was examined. The criteria are shown below.

◎… No reticulation at all ○… Nearly reticulation △… With reticulation ×… Reticulation considerably In Inventive Examples 1, 2, and 3, the difference in humidity between the drying start portion X and the drying end portion Y is 30% RH or more.

On the other hand, in Comparative Examples 1 and 2, the value of the total length of the housing / the total length of the nozzle outlet is small, and the dehumidifier is not provided, so that the humidity difference is less than 30% RH.

In Examples 1, 2 and 3 of the present invention, no reticulation occurred, and in Example 3 of the present invention having a dehumidifier, no reticulation occurred.

On the other hand, in Comparative Examples 1 and 2, reticulation occurs. In Comparative Example 1, the occurrence is remarkable.
This is because the humidity difference between the drying start part X and the drying end part Y is 30% RH.
This is probably because the above has not been achieved.

<Effects of the Invention> As described above, according to the present invention, the internal space of the housing through which the photosensitive material passes is formed in a slit shape having a small thickness in the thickness direction of the photosensitive material, so that the drying efficiency is good, In particular, the drying time can be reduced.

Also, the amount of heat given to the drying gas is reduced,
Energy consumption can be reduced because ON / OFF control is possible.

In addition, the size of the entire apparatus can be reduced by reducing the thickness of the housing and reducing the size of a fan, a heater, and the like based on a reduced supply amount of the drying gas.

Further, by setting the humidity and temperature conditions of the drying gas, reticulation of the emulsion surface of the photosensitive material can be prevented, and the film quality can be improved.

[Brief description of the drawings]

1 to 8 are longitudinal sectional views each schematically showing a configuration example of a drying apparatus used in the present invention. FIG. 9 is a sectional view taken along line IX-IX in FIG. FIG. 10 is a partial cross-sectional front view showing a configuration example of a dehumidifier using an electronic cooling element. Reference numerals 1a to 1h: Drying device 2: Casing 2a, 2b: Casing inner wall 3: Internal space 4: Inlet 4a: Inclined surface 5: Exit 6: Fan 7: Exhaust port 8, 8 ', 8 "... Nozzle 9 ... Branch duct 10, 10' ... Heater 11 ... Panel heater 12 ... Duct 121 ... Opening 13 ... Recovery port 14, 19 ... Dehumidifier 15 ... Fan 16 Heater 17 Opening 18 Water vapor permeable member 20 Sensor 21 Control unit 22, 23, 24 Power supply 30, 31, 32 Transport roller 40 Body 41 Peltier element 42 ...... absorbing portion 43 ...... heat radiating portion 44, 45 ...... opening 446 ...... pan 47 ...... drainpipe 48 ...... tank 50 ...... duct 51 ...... recovery port S ...... photosensitive material S _A ...... surface S _B …… Back side X …… Dry start part Y …… Dry end part

Claims (1)

(57) [Claims] 1. A control method for drying a photosensitive material by passing a photosensitive material through an internal space of the housing while supplying a drying gas to an internal space of the housing, the control method comprising: The internal space has a slit shape in which the thickness in the thickness direction of the photosensitive material is thin, the thickness of the internal space is 3 to 1000 times the thickness of the photosensitive material, and the total length of the housing is: It is 30 to 1000 times the total length of the air blowing section for blowing out the drying gas into the internal space of the housing, and the relative humidity near the drying start section from the relative humidity near the drying end section in the internal space. A drying control method, characterized in that the reduced value is controlled to be 30% RH or more.