GB2163370A - Apparatus for processing a photosensitive substrate - Google Patents

Abstract

Apparatus for processing a photosensitive substrate comprises, serially arranged a developing tank (12), a fixing tank (14) and a washing tank (16) through which a photosensitive substrate is carried along a path (20). One or more drop guide members (30 and 40) having inclined surfaces (32,34 and 42,44) are positioned over the tanks so that a lowermost portion (36,46) of each guide member is disposed over a respective tank. In use of the apparatus vapour evaporated from a processing tank condenses on the guide members (30 and 40) collects as drops at the lowermost portions (36,46) thereof and falls therefrom, so preventing drops of condensed solution falling onto the photosensitive substrate at crossover portions between processing tanks and also avoiding contamination of one processing solution with another, in particular contamination of the developing solution by fixing solution. <IMAGE>

Description

SPECIFICATION Apparatus for processing a photosensitive substrate This invention relates to apparatus for processing a photosensitive substrate, in particular for processing photosensitive substrates such as film, photographic printing paper and graphic materials by passing the photosensitive substrate through a series of processing tanks such as a developing tank, a fixing tank and a washing tank.

Generally, in a device for processing photosensitive materials such as a film developing device, a processing solution is maintained at a constant temperature for performing given processing. The temperature of the processing solution is particularly high, for example 30 C to 40"C, in the case of the developing solution and fixing solution, and hence vapour containing processing solution components generated from the processing solution condenses on a lid of the processing tank, and drops of the condensed solution may fall into the processing tanks and portions therebetween. Although no significant problem is caused by mixing of drops of the developing solution with the fixing solution, the developing solution is considerably degraded by the mixing therewith of drops of fixing solution, and the developing process is therefore hindered.Further, if the aforementioned drops fall onto a photosensitive substrate being carried through the portions between processing tanks during processing, irregularities in processing in the form of specks are caused and these irregularities in processing are an especially serious problem in the crossover portions between the developing and fixing tanks.

A conventional technique for preventing the condensation of processing solution vapour on a lid of processing tank is to cover the lower surface of the lid of the processing tanks with an insulating material having continuous air bubbles while providing the surfaces with fine irregularities as disclosed in Japanese Utility Model Publication (examined) No. 26356/1984. However, it is still impossible completely to prevent condensation of processing solution, and, for example where the apparatus is stopped for a long time or where the temperature difference between the interior and the exterior of the processing tanks is large, drops formed by condensation cause irregular processing of the photosensitive materials and deterioration of the developing solution.

Further, although the prevention of condensation by the method as disclosed in the above-mentioned publication can be improved by exhausting gases through exhaust pipes provided in the vicinity of the lids of the processing tanks for a given period of time during the operation and after stoppage of the processing apparatus, such structures are complicated and are not suitable especially for small-sized processing apparatus such as a bench type processing apparatus.

According to one aspect of the present invention there is provided apparatus for processing a photosensitive substrate, the apparatus comprising a plurality of processing tanks through which a photosensitive substrate is to be passed, and a surface extending over the processing tank for condensing processing solution vapour, the surface being arranged to guide drops of vapour condensed thereon so that the drops fall at a predetermined position or positions.

In a second aspect, the present invention provides apparatus for processing a photosensitive substrate, the apparatus comprising at least two processing tanks arranged in given order for passing the photosensitive substrate therethrough to process the photosensitive substrate, and at least one guide member provided over the processing tanks, the or each guide member being shaped so as to guide drops of processing solution condensing thereon to fall at a predetermined position or positions.

For a better understanding of the present invention, and to show how the same may be put into effect, reference will now be made by way of example, to the accompanying drawings, in which: Figure 1 is a side sectional view of a first embodiment of apparatus for processing photosensitive substrates in accordance with the present invention; Figure 2 is a front sectional view taken along the line 2-2 in Figure 1; and Figures 3 and 4 are side sectional views showing second and third embodiments, respectively, of the present invention.

Referring now to the drawings, Figures 1 and 2 illustrate a first embodiment of apparatus in accordance with the present invention for processing photosensitive substrates such as photographic film, photographic printing paper, graphic materials and the like.

Figure lisa side sectional view and Figure 2 is a schematic front sectional view taken along the line 2-2 in Figure 1 of the first embodiment, components such asfeed rollers being omitted in Figure 2.

As shown, the apparatus comprises a developing tank 12, a fixing tank 14 and a washing tank 16. An exposed photosensitive substrate is supplied from a feed tray 18 and is carried successively through the developing, fixing and washing tanks 12,14 and 16 along a carriage path 20. The processed film emerging from the washing tank 16 is dried in a drying section 22 by hot air from a blower which comprises a pair of fans 24 and a heater 26, and is then discharged through a discharging port 28.

A first drop guide member 30 having inclined portions 32 and 34 is arranged over the developing tank 12 and a fixing tank 14 so that a lowermost portion 36 thereof is positioned over the fixing tank 14. A second drop guide member having inclined portions 42 and 44 is arranged over the washing tank 16 so that a lowermost portion 46 thereof is positioned over the washing tank 16.

During use of the apparatus a space 29 defined over the repective processing tanks 12, 14 and 16 is filled with vapour containing processing solution which has evaporated from the respective processing solutions. The vapour condenses and forms drops on the lower surfaces of the drop guide members 30 and 40. However, the drops of condensed vapour collect at the lowermost portions 36 and 46 of the inclined portions 32, 34, 42 and 44 of the drop guide members 30 and 40 ans so fall in the fixing tank 14 and the washing tank 16, respectively. Thus, no drops can fall on the photosensitive materiai being carried through crossover portions between the processing tanks to cause irregular processing, and moreover no drops containing components of the fixing solution can fall into the developing tank 12 tgo deteriorate the developing solution.

Figure 3 is a side sectional view showing a second embodiment of the present invention. In this embodiment, a drop guide member 50 having inclined portions 52 and 54 is arranged over the developing tank 12, the fixing tank 14 and the washing tank 16 so that a lowermost portion 56 thereof is positioned over the washing tank 16.

During use of the apparatus shown in Figure 3, drops condensing in the lower surface of the drop guide member 50 collect at the lowermost portion 56 joining the inclined portions 52 and 54 of the waterdrop guide member 50 and so fall into the washing tank 16.

Figure 4 is a side sectional view showing a third embodiment of the present invention. In the embodimentshown in Figure 4, drop guide members 60,70 and 80 each have respective inclined side walls 62 and 64,72 and 74, and 82 and 84 so that each guide member 60,70 and 80 has a respective lowermost portion 66,76 and 86. The lowermost portions 66,76 and 86 are arranged over the developing tank 12, fixing tank 14 and washing tank 16, respectively.

In the arrangement shown in Figure 4, most of the vapour generated from the processing tanks 12, 14 and 16 condenses on the lower surfaces of the associated drop guide member 60,70 and 80, respectively, and the drops formed thereon collect at the respective lowermost portions 66,76 and 86 of the drop guide members and therefore fall back into the processing tank from which the drops originally came. Hence no irregular processing is caused by drops of condensed processing solution falling on the photosensitive substrate being carried through crossover portions.

To avoid some of the vapour generated from the respective processing tanks 12, 14 and 16 condensing on the lower surfaces of the adjacent drop guide members, and drops thereof falling into adjacent processing tanks, the inclined portion 74 of the guide member 70 located over the fixing tank 14 which is close to the developing tank 12 extends beyond the crossover portion between the fixing and the developing tank so that a portion thereof is disposed over the developing tank and vapour generated from the fixing tank 14 cannot condense on the drop guide member 60 located overthe developing tank 12 but condenses on the lower surface of the inclined portion 74 of the drop guide member 70. Therefore no drops containing components of the fixing solution fall into the developing tank 12 to deteriorate the developing solution.

Although in each of the above described embodiments the inclined portions of the drop guide members are flat surfaces, the inclined portions need not necessarily be flat or planar surfaces but can, for example, be convexly or concavely curved surfaces.

Further, although in each of the arrangements described above each of the drop guide members is inclined in the direction in which the photosensitive substrate is carried, the guide members may, needless to say, be inclined in a direction perpendicular to the direction of carriage of the substrate, and may further be of a conical or polyconical form so that the lowermost portion of a guide member does not project over the tanks.

By using processing apparatus in accordance with the present invention no drops formed by condensation fall on crossover portions between processing tanks and hence irregular processing of photosensitive materials can effectively be prevented.

Further, since no drops containing components of fixing solution fall into the developing tank, deterioration of the developing solution can be prevented.

In addition, since the condensed drops of solution can be made to fall immediately, staining and corrosion ofthe apparatus is prevented.

Thus, the apparatus described above enables the positions at which condensed drop or droplets of processing solution fall back into the processing tanks to be controlled by providing drop guide members over the processing tanks, the guide members being arranged to project toward the tanks and the lowermost portions of the drop guide members being arranged in positions in which no problem is caused by falling of drops, such as positions are the central portions of the processing tanks.

The drops formed by condensation on the lower surfaces of the drop guide members are collected at the lower end portions of the drop guide members and fall into the processing tanks located directly under the said lower end portions so that irregular processing of a photosensitive substrate being carried through crossover portions between processing tanks is prevented and deterioration of developing solution by drops containing components of fixing solution is prevented.

Claims (20)

1. Apparatus for processing a photosensitive substrate, the apparatus comprising a plurality of processing tanks through which a photosensitive substrate isto be passed, and a surface extending over the processing tank for condensing processing solution vapour, the surface being arranged to guide drops of vapour condensed thereon so that the drops fall at the predetermined position or positions.

2. Apparatus according to claim 1, wherein the surface is shaped to guide drops of vapour condensed thereon so that the drops fall at a predetermined position or positions.

3. Apparatus according to claim 2, wherein the surface is shaped to guide drops of vapour condensed thereon so that the drops fall into a selected processing tank or tanks.

4. Apparatus according to claim 3, wherein the surface is formed by one or more guide members, the or each guide member being shaped so as to extend downwardly toward the or a respective processing tank, a lowermost portion of the or each guide member being disposed over the or the respective processing tank.

5. Apparatus for processing a photosensitive substrate, the apparatus comprising at least two processing tanks arranged in given order for passing the photosensitive substrate therethrough to process the photosensitive substrate, and at least one guide member provided over the processing tanks, the or each guide member being shaped so as to guide drops of processing solution condensing thereon to fall at a predetermined position or positions.

6. Apparatus according to claim 4 or 5, wherein the or each guide member is so provided that the lower end portion thereof is opposed to a portion other than a crossover portion between adjacent procesing tanks.

7. Apparatus according to claim 4, 5 or 6, wherein the or each guide member is formed by two inclined intersecting wall portions.

8. Apparatus according to claim 7, wherein the two wall portions of the or each guide member intersect in a direction substantially parallel to a direction along which a photosensitive substrate is passed.

9. Apparatus according to claim 7, wherein the two wall portions of the or each guide member intersect in a direction substantially perpendicular to a direction along which a photosensitive substrate is passed.

10. Apparatus according to claim 7,8 or 9, wherein the wall portions are planar.

11. Apparatus according to claim 7,8 or 9, wherein the wall portions are convex and/or concave.

12. Apparatus according to claim 4,5 or 6, wherein the or each guide member is substantially conical in shape.

13. Apparatus according to claim 4,5 or 6, wherein the or each guide member is shaped so as to have a plurality of substantially conical portions depending therefrom.

14. Apparatus according to any one of claims 4 to 13, wherein the guide members are integrally formed.

15. Apparatus according to any one of claims 4 to 14, wherein one guide member is provided, the lowermost portion thereof being disposed over a washing tank of the plurality of processing tanks.

16. Apparatus according to any one of claims 4 to 14, wherein two guide members are provided, the lowermost portion of one guide member being disposed over a washing tank and the lowermost portion of the other guide member being disposed over a fixing tank ofthe plurality of processing tanks.

17. Apparatus according to any one of claims 4 to 14, wherein three guide members are provided, the lowermost portion of each guide member being disposed over a respective one of a developing tank, a fixing tank and a washing tank ofthe plurality of processing tanks.

18. Apparatus according to claim 17, wherein the guide member having the lowermost portion thereof disposed over the fixing tank extends upwardly from the said lowermost portion over part of the adjacent developing tank.

19. Apparatus for processing a photosensitive substrate, substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 and 2 or Figure 3 or Figure 4 of the accompanying drawings.

20. Any novel feature or combination of features described herein.