JP2870592B2 - Sheet material handling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a sheet handling apparatus and, more particularly, to an apparatus that includes at least a pair of mutually offset rollers for forming a nip in a sheet path. More particularly, the invention relates to the structure of the rollers used in such devices.

[0002]

BACKGROUND OF THE INVENTION Sheet handling equipment is utilized in a number of forms, such as printing machines, photographic processors, paper forming and processing machines, textile forming and processing machines, and the like. In such an apparatus, a relatively flexible material, such as paper, fabric, metal sheet or synthetic material sheet, is usually a pair of rollers offset from each other, either as a web rewound from a roll or in the form of a cut sheet. Through the nip formed by the For example, processing apparatuses for photographic sheet materials such as X-ray films, pre-sensitized plates, graphic technology films and papers, and offset plates, such as developing solutions, fixing solutions and washing solutions,
Several tanks containing the processing solution are provided. The sheet material to be treated is transported sequentially through these tanks and then optionally to a drying unit.

[0003] It is often advantageous that rollers incorporated in such machines act as drive rollers and serve to advance the sheet material through the device. In order to fully meet these requirements, the elasticity of the rollers is important. Typically, such a roller comprises, for example, a rigid core having a layer of an elastomeric material. If the elastomeric material is too stiff, the pressure exerted by the rollers on the sheet material may not be uniform. Further, when the sheet material is in contact with the processing liquid, the squeegee properties across the edge of the sheet material may not be optimal, resulting in an unacceptable level of carryover. On the other hand, if the elastomeric material is too soft,
Degrades rapidly due to wear. Attrition results from contact between one roller and the other and / or between one roller and the sheet material. Some sheet materials wear particularly on the rollers, especially on sheet materials that contain abrasives, such as fillers, such as titania on paper.

[0004]

OBJECTS OF THE INVENTION It is an object of the present invention to provide a sheet handling apparatus incorporating rollers that can withstand abrasion without significant loss in operating characteristics.

[0005]

SUMMARY OF THE INVENTION According to a first aspect of the invention, there is provided a sheet material handling apparatus including a roller biased toward a reaction surface to form a nip in a sheet material path.
A sheet handling apparatus is provided wherein the roller comprises an outer region of an elastomeric material, at least a portion of which contains potassium titanate whiskers.

The reaction surface on which the rollers are biased to define the nip is typically the surface of another roller, or the reaction surface is in the form of a low coefficient of friction belt or fixed surface. Where this general description refers to the use of two rollers, it is understood that the second pass defining roller may be replaced by any other reaction surface, as described above.

[0007] Such an apparatus is preferably of the type in which the rollers are in contact with a sheet material processing liquid, and in particular for wet processing of photographic sheet materials comprising at least one processing tank in which pairs of rollers are incorporated. It is a device adapted to If the reaction surface on which the rollers are biased to define the nip is the surface of another roller, the above roller requirements preferably also apply to this second roller.

According to a second aspect of the invention, the sheet material path (1
20) In a method of processing photographic sheet material by passing the sheet material along a sheet material path through a device including a roller biased toward a reaction surface to form a nip at 20), wherein the rollers are A method comprising providing an outer region of an elastomeric material, at least a portion of which comprises a potassium titanate whisker.

In conventional photographic processing equipment, the sheet material is transported along a generally horizontal feed path, and the sheet material typically passes below the surface of each processing solution and above a partition between the tanks. It passes from one tank to another via a circular feed path.

EP-A-410500 (Agfa Ge
in a system for developing an aluminum lithographic printing plate of the type disclosed in US Pat.
The apparatus comprises a housing in which a pair of processing rollers pivotally supported on a roller shaft is supported within the housing. The processing rollers are positioned substantially parallel to one another in line contact. Means for feeding the photographic sheet material between the rollers are provided. The roller shafts are offset from one another and exert pressure on the photographic sheet material passing between the rollers.

A processing machine having a substantially vertical orientation is also proposed, in which a plurality of vessels are mounted one above the other, each vessel having an opening in the upper part acting as a sheet material outlet or inlet, and a sheet material inlet. Or with an opening in the bottom that acts as an outlet. In the present context, the term "substantially vertical" means that the sheet material moves along a path from the entrance to the exit that is exactly vertical or has a vertical component that is greater than the horizontal component. The use of vertical orientation for the device leads to a number of advantages. In particular, the device
It occupies only a small part of the floor space occupied by the conventional horizontal arrangement. In addition, the sheet transport path in a vertically oriented device is substantially straight, as opposed to a generally circular path in a horizontally oriented device. As a result of the straight path, the scratch sensitivity of the material is independent of the stiffness and thickness of the material.

In a vertically oriented apparatus, it is important to avoid or at least minimize leakage of processing liquid from one tank to another and carryover as the sheet material passes through the apparatus. US Pat. No. 4,166,689 (Sch
ausberger et al., Agfa-Gevaert A
(Assigned to G) describes a device in which liquid leaks from the lower opening and is blocked by a tank of a closure with two squeegees located in the tank above a horizontal passage aligned with the lower opening. One or more drive rollers in the vat close the lower opening and also serve to transport the sheet material along a vertical path extending between the vat openings.

In both types of processing equipment, the rollers are used in pairs offset from one another, between which the sheet material passes and acts as a seal between the processing vessels of the processing equipment, ie, one When passing from the processing tank to the next tank,
Remove excess processing solution from the sheet. This reduces processing solution carryover, thereby reducing contamination and wear. Good removal of the processing liquid is also needed to reduce the drying time of the sheet material after the last process bath, thus reducing energy use.

In a preferred embodiment of the invention, the outer region comprises a sleeve portion and one or both ends. Potassium titanate whiskers are contained at the sleeve portion or at one or both ends. It is particularly advantageous for potassium titanate whiskers to be included at each end of the outer region when the roller is mounted between sealing surfaces in contact with the end face of the roller.

A typical roller has a core with a coating of an elastomeric material, but it is also possible for the roller to be elastomeric throughout its cross section. When the sheet material exits the given liquid processing tank, it is necessary to remove the liquid adhering on the sheet material as efficiently as possible, to prevent carryover of the liquid to the next processing tank, and to prevent the sheet from being transferred to the next processing tank. Reduces edge effects arising from heterogeneous chemicals on the material. This is true whether the device is in a horizontal or vertical configuration. For this to work properly, the rollers must exert a sufficiently uniform pressure over the entire width of the sheet material. Further, in order to reduce the edge effect, it is desirable that the surfaces of the opposed rollers are in contact with each other beyond the edge of the sheet material. Regarding this problem, the rollers used in conventional processing equipment have a length of, for example, 400 mm or more and a diameter of 24 to 60 mm. The sheet material is typically
Widths from a few millimeters to a maximum of 2 m and 0.05 mm to 0.1 mm.
It has a thickness of 5 mm. In view of the nature of the elastomeric material, it is practically impossible to completely eliminate the gap between the roller surfaces at the edge of the sheet material as it passes through the nip. Preferably, the roller surfaces are in contact with each other within the shortest possible distance from the edge of the sheet material, ie, the size of the leak zone is minimized. It is important, however, that the force between the rollers is sufficient to prevent leakage when no sheet material is passing. However, the force must not be so high as to penetrate the physical damage to the sheet material as it passes through the nip.

In order to equalize the pressure exerted on the sheet material over the width by the rollers, the rollers do not have a precise cylindrical configuration, but rather the rollers have a radial dimensional profile that varies along their length. It was proposed to prepare. This is achieved by polishing the elastomer to provide a predetermined profile on the roller.

The potassium titanate whiskers are generally of the formula K ₂ O. TISMO represented by nTiO ₂ , in particular
Known as TISMOD (n = 8) in the art. It is a fine whisker with a general whisker diameter of 0.3-0.6 μm and a whisker length of 10-20 μm. Although its use in composite plastics materials has been proposed, its beneficial properties, especially reduced elastomer wear and reduced friction, when incorporated in the elastomeric outer region of the roller of the sheet material handling device, have not previously been observed. .

The outer region of the roller is formed from an elastomeric material selected from ethylene / propylene / diene terpolymer, silicone rubber, polyurethane, thermoplastic rubber, styrene butyl rubber, nitrile butyl rubber, the elastomeric material optionally being Doped with potassium titanate whiskers. A surface modifier selected from PTFE (polytetrafluoroethylene) particles, carbon fiber, glass fiber, glass beads and mixtures thereof is included in the elastomer material to reduce abrasion, reduce friction and self-clean. Thereby further modifying the surface.

Potassium titanate is incorporated in the elastomeric material at a level of 5 to 30% by weight, such as 10% to 20%. High levels of contamination significantly reduce the flexibility of the elastomer. Unless incorporated at levels high enough to have a detrimental effect on the sheet material or the chemical reactions occurring, potassium titanate whiskers are:
Selected from carbon fibers and fibers formed from silicon carbide, titanium carbide, boron carbide, alumina, zirconia, zinc oxide, ferrite derivatives, wollastonite, mica, clay material, silicon nitride, boron nitride and titanium boride Partially replaced by one or more alternative whisker materials.

Each roller further comprises an inner region of elastomeric material having a lower elevation than the outer region.
Although the two regions of the elastomeric material are usually constituted by distinct layers, the use of a single layer of the elastomeric material formed to vary in hardness over its thickness is an advantage of this embodiment of the invention. In range.

The Shore A hardness of the inner region is smaller than 50, preferably 15 to 45, while the Shore A hardness of the outer region is larger than 25, preferably 40 to 45.
90. Although the inner and outer regions are constituted by distinguishable layers, the difference in Shore A hardness between the inner and outer layers is at least 5, and most preferably at least 10. Elastomer materials with low Shore A hardness
While providing elastomer properties consistent with the goal of low carryover, low molecular weight compounds tend to diffuse into the treatment bath during use, resulting in loss of these elastomer properties and poor chemical and physical abrasion resistance . The provision of an outer region of an elastomeric material having a high Shore A hardness reduces the negative effects and enables polishing to the desired surface quality, surprisingly without significantly increasing the carryover.
More specifically, optimal polishing of an elastomeric material is necessary to stabilize its surface roughness, thereby improving the hydrophilicity of the material, and also to drive the roller by reducing its rolling resistance. Reduced torque. The use of relatively hard elastomeric materials
Improves stability to oxygen and ultraviolet light, reduces evaporation of elastomeric compounds from surfaces, and reduces diffusion of processing solutions through materials. Therefore, the performance and useful life of the roller
Optimized.

Preferably, the roller comprises a rigid core and the inner region is an intermediate region located above the core. The inner region is in direct contact with the core and the outer region.
Preparation of the rigid core involves transmitting power to the rollers in a conventional manner. However, the preparation of the rigid core is not essential and the roller can be driven externally by frictional contact between the outer surface of the roller and a suitable drive means such as a separate drive roller. .

[0023] Preferably, the outer elastomeric material region extends over the end face of the inner elastomeric material region. This is preferred to reduce or prevent degradation of the elastomeric material in the inner region due to exposure to the processing liquid.

The portion of the outer region extending above the end face of the inner region is shaped to provide a space in which the elastomeric material of the coating is deformed as a result of the sealing force between the roller and the sealing surface of the device.

Both rollers have an inner region of relatively low hardness elastomeric material and an outer region of relatively high hardness elastomeric material located above the inner region. In fact, it is common for two identical rollers to be used. However, the second roller need not be so configured, for example, a roller without an elastomeric coating.

When the inner and outer regions are constituted by distinguishable layers, the inner layer is between 10% and 20% of the roller diameter.
%, 5% to 35%, ie 40 mm
4-8 mm for a typical roller having a diameter of
Is at least 1.0 mm. The outer region has a thickness of 1% to 10% of the roller diameter, i.e. at least 0.2 mm for a typical roller. Below this thickness, the elastomeric effect is lost and polishing to the desired profile becomes difficult or impossible. It is possible to add further regions, but usually there are no other regions, so that the inner region is in direct contact with the core and the outer region. It is noted that the core is primed or treated with an adhesive to ensure a good bond with the inner region of the elastomeric material.

Preferably, the core is 50 GPa to 300 GPa.
It has a flexural modulus of GPa. Suitable materials for the rigid core are metals, such as stainless steel, non-ferrous alloys, titanium, aluminum or composites thereof. In one embodiment of the invention, the core is hollow. Alternatively, the core is solid.

In a preferred embodiment of the invention, the portion of the outer region extending above the end face of the inner region provides a space in which the elastomeric material of the coating is deformed as a result of the sealing force between the roller and the sealing surface of the device. It is shaped as follows. Alternatively, the sealing surface is provided with a space for the same purpose. The outer region is formed in two parts. The first portion extends over the end surface of the inner region, while the second portion extends along the outer surface of the roller. The two parts of the outer region are formed by a separate vulcanization step.

In use, in a photographic sheet material processing apparatus, one roller is positioned in parallel contact with another roller to form a squeegee pair. In order to obtain good processing quality, the rollers at the outlet of each tank of the apparatus exert a load of 0.001 to 1.0 N / mm roller length, preferably about 0.025 to 0.5 N / mm, and It is convenient to remove the waste material and the load is actually applied to each end of the roller. For this, Laura
They are offset from one another and take advantage of the inherent elasticity of the elastomeric material. Alternatively, a spring acting on the end of the roller shaft is used. The spring is replaced by alternative equivalent compression means, such as, for example, a pneumatic or hydraulic cylinder.

In certain embodiments of the invention, the inner and / or outer regions have a variable thickness to provide the roller with a radial dimensional profile that varies along its length. This is achieved by polishing each area to provide a predetermined profile on the roller.
Alternatively, the rigid core is provided with a diameter that varies along its length. Preferably, both rollers of the roller pair have the same radial dimensional profile for ease of manufacture. Ideally, the radial dimensional profile of each roller is such that, with respect to the pressing force applied to the rollers, the force applied to the sheet material by the rollers is substantially uniform in its width.

The radial dimension of each roller is ideally
Decreasing towards its end, ie a convex profile,
Above all, a parabolic profile. Ideally, the radial profile of such a roller is such that the force exerted by the roller on the sheet material passing through the nip is approximately uniform in its width.

In a preferred embodiment of the invention, the rollers are substantially equal in length. One or both of the rollers constitute a drive roller for driving the sheet material along the sheet material path. Alternatively, the rollers are free to rotate and alternative drive means are provided for driving the photographic sheet material through the device.

The invention comprises an apparatus having a plurality of processing tanks arranged to define a substantially horizontal sheet material path, and a plurality of processing tanks arranged to define a substantially vertical sheet material path. It is applicable to a device that performs

[0034]

The invention is not intended to limit the invention,
The following exemplary embodiments will be described with reference to the accompanying drawings.

Referring to FIG. 1, not to scale, the roller 1
2 comprises a stainless steel rigid core 56, an inner or intermediate region 58 of elastomeric material located above the core, and an outer region 60 of elastomeric material located above the intermediate region. No other area exists, and as a result,
Intermediate region 58 is in direct contact with core and outer region 60.

In the exemplary embodiment described, the core 56 is in the form of a hollow stainless steel cylinder having an outer diameter of 25 mm and a wall thickness of 3 mm.

The intermediate region 58 has a thickness T _{1 of} 6.5 mm (equal to about 16% of the roller diameter) and has a shore A of 24
It is formed from EPDM having hardness.

The outer region 60 is also formed from EPDM, in this case having a Shore A hardness of 50. Outer region 60, to provide a radial dimension profile which varies along its length to a roller, has a variable thickness T _2.

To form the roller shown in FIG. 1, the intermediate region 58 is coated with an adhesive primer over the core and then by applying a non-vulcanized EPDM.
Formed on a rigid core. Then a plastic tape is firmly adhered over the EPDM so as to push out the excess air. The assembly is autoclaved for 1-2 hours at a pressure of 6-7 bar and a temperature of 160-180 ° C in the presence of sulfur or peroxide to ensure vulcanization. After removing the assembly from the autoclave and cooling, the intermediate region 58 is polished to the desired profile. The outer region 60 is then formed by a similar process, with the desired profile, in this example, the thickness of the outer region 60 varying from 0.5 mm at each end of the roller to 1.0 mm at the center of the roller. It is subsequently processed by machining to ensure a physical profile, which results in 3
Gives a total roller diameter varying from 9 mm to 40 mm at the center. The rollers generally have a length of 850 mm.

FIG. 1 shows two possible embodiments of the invention. As shown at the right end of FIG. 1, the separating portion 64 of the outer region extends over the end face 68 of the inner region, and this portion of the outer region of the elastomeric material has a TIS of about 15% by weight.
EPD mixed with MOD potassium titanate whisker
M is formed. The portion 64 is shaped to provide a space 65 in which the elastomeric material of the coating is deformed as a result of the sealing force between the roller and the sealing surface of the device. In this embodiment, the outer region thus comprises two parts: a sleeve portion 62 arranged along the outer surface of the roller and an end 6 extending above the end face 68 of the inner region 58.
4 formed in. The two parts of the outer region are formed by separate vulcanization steps. In the embodiment shown at the left end of FIG. 1, the outer region 60 itself extends over the end face 68 of the inner region 58. In this embodiment,
The entire outer region 60 has a TISMOD of about 15% by weight.
Formed from EPDM mixed with potassium titanate whiskers. In both of these embodiments, the shaft 1
6, 18 are suitably welded or integral to the end of the core 56. Whatever structure is used for the end of the roller, the intermediate region 58 is masked from the processing liquid used in the device incorporating the roller and the chemical in the more chemically sensitive material of the intermediate region is used. Reducing erosion is advantageous.

Referring to FIG. 2, the above-mentioned EP-A-41
A portion of a photographic sheet material processing apparatus of the type described at 0500 is shown. The processing device includes a general rectangular housing 10 including a rectangular metal main frame (not shown in FIG. 2 for clarity) to support various sections of the device.
Mounted inside. The apparatus includes a number of processing vessels, wherein the sheet material to be processed is passed from one vessel to the next by a squeegee roller pair serving as a drive roller. One such roller pair, an upper squeegee roller 12 and a lower squeegee roller 14, is shown in FIG. The upper roller 12 is configured as shown in FIG. The lower roller 14 is similarly configured. Roller 12
And 14 are positioned substantially parallel and in line contact with each other. The upper roller 12 is fixed at respective shafts 16 and 18 for rotation, and the lower roller 14
Are fixed at respective shafts 20 and 22 for rotation. Roller shafts 16, 18, 20, 22
Are attached to each end in bearings held in respective sub-frames 24.

The drive 26 for the rollers comprises a mechanical transmission for driving the processing roller 22 and a set of co-operating gears located at one end of the same side of both roller shafts 16,20. Is provided. The upper processing roller 12 is driven by a worm screw 34 by a drive shaft 32 that links all the upper rollers in the apparatus.
And at one end through the worm wheel 36. The lower processing roller 14 is provided with another helical gear 40.
Is driven by a helical gear 38 that meshes with. The drive shaft 32 is preferably driven by an electric motor having an encoding disc system (not shown) to control the speed and progressive horizontal position of the sheet material.

The coordinates of the upper processing roller 12 are defined by end bearings 42 and 44. The lower roller 14 slides vertically in a guide (not shown) in the sub-frame 24.
It rotates on one bearing plate 46, so that the lower roller 14 is free to move with respect to the upper roller 12.

The roller shafts are offset from one another to exert pressure on the photographic sheet material as it passes between the rollers. The compression springs 48, 50 deflect the lower roller 14 toward the upper roller with a force of up to 400N at a roller length of about 850mm.

The profile of the roller 12 is the lower roller 1
4 is similarly constructed, and when a pressing force of 380 N / 850 mm is applied by the springs 48, 50, the aluminum lithographic sheet material having a thickness of 0.1 to 0.4 mm passes between the rollers. The force applied appears to be approximately uniform in its width.

The roller displacement device generally indicated by reference numerals 28 and 30 is also indicated. Cam shaft 52, 5
4 control the vertical displacement of the displaceable processing roller 14, each driven by a synchronous electric motor having an encoding disc system (not shown).

The rollers shown in FIG. 1 are also suitable for use in a vertical processor, one embodiment of which is shown in FIG. As shown in FIG. 3, each vat 112 includes a housing 114 having a generally rectangular cross-section and is shaped to provide an upper portion 115 having an upper opening 117 and a lower portion 116 having a lower opening 118. The upper opening 117 defines a sheet material inlet, and the lower opening 118 defines a sheet material outlet. The inlet and outlet define a substantially vertical sheet material path 120 through the tub 112, and the sheet material 122 moves downward, as indicated by arrow A. The sheet material preferably has a width that is at least 10 mm less than the length of the nip, allowing a gap of at least 5 mm between the edge of the sheet and the adjacent limit of the nip, thereby minimizing leakage. Each tank 1
12 includes a processing liquid 124, and a passage 126 in the housing 114 is provided as an inlet of the processing liquid 124. The lower opening 118 is closed by a pair of rotatable rollers 128, 130 pivotally supported in the device.

Each roller 128, 130 is of the squeegee type shown in FIG. 1 and comprises a stainless steel hollow core 56 having inner and outer elastomeric coatings 59, 60. The rollers 128, 130 are mounted between end plates 162 which form a sealing surface in contact with the end surfaces 66 of the rollers. The rollers 128, 130 are biased toward each other with sufficient force to provide a liquid-tight seal without passing through the photographic sheet material 122 without damage. Roller 128, 1
The contact line between 30 defines a nip 136. The rollers 128, 130 are coupled to driving means (not shown) to form a drive roller for driving the seal 122 along the seal path 120.

In the illustrated embodiment, each roller 12
8, 130 are in sealing contact along their length, each stationary sealing member 138, 139 is supported on a sealed support 140 secured to the housing 114 of the tank 112, and the processing liquid 124 is provided on rollers 128, It is held in the tank 112 by 130 and the sealing members 138, 139.
The sealing members 138, 139 are formed of PTFE and have a composite structure. The sealing members 138, 139 are secured to the sealing support 140 by a suitable water and chemical resistant adhesive, such as a silicone adhesive. The use of a relatively hard material for the outer region 60 of the roller reduces the wear resistance between the roller surface and the sealing members 138,139.

Upper and lower housing portions 115, 116
Are provided with flanges 119, 121, respectively, for mounting the tank 112 directly above or below the same or similar other tanks 112 ', 112 ", as partially shown in broken lines in FIG. Upper housing part 1
15 is shaped with respect to the lower housing part 116 so as to provide a substantially closed connection between adjacent vessels. Thus, the processing liquid from the tank 112 is
8 and 130 and the sealing members 138 and 139
The vapor from the lower tank 112 "is prevented from entering the tank 112 or leaking into the environment. This configuration has the advantage that the processing liquid in one tank 112 is not contaminated by the contents of the adjacent tank and evaporation, oxidation and carbonization are significantly reduced since the processing liquid is in a closed system.

The upper part 115 of the housing 114 is shaped to define a leak tray 142. The processing liquid passing through the roller nip of the next higher tank 112 ′
As the sheet material 122 passes, it drips from the rollers of the tank and falls into a leak tray 142 from where it is collected and recycled as desired. The distance H between the surface 125 of the liquid 124 and the nip of the rollers of the next upper tank 112 '
Is as small as possible. Each of the end plates 162 is a roller 1
The end plates are shaped to have a perimeter around the shafts 28, 130 to bring the end plate into face-to-face contact with the end face 66 of the roller. At its lowest point, the edge 166 is
Below the level. The end face 66 of the roller, as measured on the surface of the roller, is between
It is biased against end plate 162 with a contact force of 500 g / cm.

The end plates 162 each have an aperture 174.
, The lower edge of which is located below the top of the rollers 128, 130 to allow a large volume of processing liquid to drain from the bath at each end and recirculate as desired.

The main features and aspects of the present invention are as follows.

1. A photographic sheet material wet processing apparatus for wet processing of photographic sheet material comprising at least one processing tank in which a roller biased toward a reaction surface is located to form a nip through which the sheet material path extends. A photographic sheet material wet processor comprising an outer region of an elastomeric material, at least a portion of which includes a potassium titanate whisker.

2. The device of claim 1, wherein the outer region comprises a sleeve portion and at least one end.

3. The device of claim 2 wherein said potassium titanate whisker is contained in said sleeve portion.

4. The device of claim 2 wherein said potassium titanate whisker is contained at said at least one end.

5. An apparatus according to claim 4, wherein the roller is mounted between sealing surfaces in contact with the end face.

6. The apparatus of claim 1, wherein the roller comprises an inner region of an elastomeric material having a lower hardness than the outer region.

7. The device of claim 6, wherein the outer region extends over an end surface of the inner region.

8. A portion of the outer region extending above the end face of the inner region is shaped to provide a space in which the elastomeric material of the coating is deformed as a result of a sealing force between the roller and a sealing surface of the device. An apparatus according to claim 7, wherein

9. The outer region is an ethylene / propylene / diene terpolymer, silicone rubber, polyurethane,
The device of claim 1 formed from an elastomeric material selected from thermoplastic rubber, styrene butyl rubber, and nitrile butyl rubber.

10. The apparatus of claim 1, wherein the reaction surface is further defined by another roller.

11. A method of wet processing a sheet material by passing the photographic sheet material along a sheet material path of an apparatus that includes rollers biased toward a reaction surface to form a nip where the sheet material path extends. The method wherein the roller comprises an outer region of an elastomeric material, at least a portion of which comprises a potassium titanate whisker.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a processing roller suitable for use in a horizontal photographic material processing apparatus.

FIG. 2 uses the processing rollers shown in FIG.
1 is an elevational view of a portion of a horizontal photographic material processing apparatus according to the present invention.

FIG. 3 is a cross-sectional view of one of the tanks of the vertical processing apparatus according to the present invention, in which the adjacent tanks are partially indicated by broken lines.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Housing 12 Roller 32 Drive shaft 56 Core 58 Intermediate area 60 Outer area 68 End face

────────────────────────────────────────────────── (5) References JP-A-8-114905 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03D 3/00-17/00

Claims (2)

(57) [Claims] 1. A photographic sheet material wet process for wet processing a photographic sheet material comprising at least one processing tank in which a roller biased toward a reaction surface is positioned to form a nip through which the sheet material path extends. An apparatus, wherein the roller comprises an outer region of an elastomeric material, at least a portion of which comprises a potassium titanate whisker. 2. The wet processing of the sheet material by passing the photographic sheet material along a sheet material path of an apparatus including a roller biased toward a reaction surface to form a nip over which the sheet material path extends. The method wherein the roller comprises an outer region of an elastomeric material, at least a portion of which comprises a potassium titanate whisker.