JPH0223858B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a processing apparatus suitable for photographic materials, particularly long photographic materials such as rolls.

(B) Prior art and its problems Photographic materials using silver halide emulsions as light-sensitive components have an extremely large number of uses and types.

Furthermore, developing processing of photographic materials is often performed using automatic processors, and various automatic processors are known depending on the type of photographic material.

Today, silver halide photographic materials have come to be used in information recording systems such as cathode ray tube (CRT) display systems and laser scanner systems, which immediately display information output from electronic computers as characters and graphics.

The photographic materials used in such systems are
Generally, after information has been recorded (exposed), the material is stored in a roll in a cassette, and this cassette is set in an automatic processor for development. Therefore, this development process often results in long objects ranging from several meters to several tens of meters.

A conventional developing device will be described with reference to FIG. 1, which is shown as a developing device of the present invention.

That is, the exposed photographic material 2 in the cassette 1 is conveyed to the developing tank by a roller pair 3 with the photosensitive surface facing up to a squeeze roller pair 4, and this squeeze roller pair 4 transfers the photograph to the next processing tank. It has the function of transporting materials. In FIG. 1, a plurality of freely rotatable guide rollers 5 for controlling the advance of the photographic material are provided between the carry-in roller pair 3 and the squeeze roller pair 4, but guide plates or roller pairs may also be provided. One roller of each roller pair is a driving roller, and both ends of the roller pair are connected by springs. Each roller pair is synchronized.

The rollers are typically made of an elastic material (e.g., rubber) to avoid damage to the photographic material and to improve conveyance of the photographic material, and each roller of the pair is made of equal diameter.

However, when a long photographic material is processed using the above-mentioned automatic processor, wrinkles begin to appear in front of the squeeze roller pair 4 due to the meandering of the photographic material after the processing reaches a certain length.
There is a serious drawback that processing cannot be performed. The reason for this is that the photographic material between the pair of input rollers 3 and the pair of squeeze rollers 4 does not suffer from the above-mentioned defects because the tension is applied by the cassette 1, whereas the photographic material between the pair of input rollers 3 and the pair of squeeze rollers 4 is in a state where no tension is applied, and it is thought that even if the nip pressure on the left and right sides of the pair of squeeze rollers differs slightly, the photographic material will gradually move toward the side where the nip pressure is higher, causing wrinkles. Therefore, even if a pair of guide rollers is provided in the processing tank, if the length of the photographic material to which no tension is applied exceeds a certain level, wrinkles will similarly occur due to meandering. Furthermore, it can be said that the above problem is more likely to occur in photographic materials having a wide width close to the length of the squeeze roller pair (ie, the distance between both ends of the roller pair that determines the nip pressure of the roller pair), such as a lithographic printing plate.

(C) Object of the Invention An object of the present invention is to provide a photographic processing apparatus that does not generate wrinkles due to meandering even when processing a long photographic material.

(D) Structure of the Invention The above-mentioned object of the present invention is to provide a photographic processing apparatus having at least one photographic processing tank and a plurality of pairs of conveying rollers for photographic materials, in which one roller has a surface that is smooth with respect to the other roller. A photographic processing apparatus comprising at least one pair of large conveyance rollers, and configured such that the relative rotational speed of the pair of rollers is greater than that of the pair of conveyance rollers on the photographic material supply side of the pair of rollers. achieved by.

A detailed description will be given below with reference to the drawings.
FIG. 1 is a schematic cross-sectional view of essential parts showing an example of a photographic processing apparatus of the present invention. The outline of the developing device is the same as the conventional developing device described with reference to the developing device of FIG. 1, and the characteristics of the developing device of the present invention are as shown in FIG. The point is that the relative speed was changed as described. For example, one roller 4a of the pair of squeeze rollers is made of an elastic roller as in the past. In contrast to the roller 4a, the roller 4b is made of a material with a high slipperiness on its surface. That is, when the roller 4a is a rubber roller, the roller 4b is selected from resin (for example, phenol resin, etc.) or metal (for example, stainless steel) with high surface smoothness. The materials of the rollers 4a and 4b may be reversed. The slipperiness of rollers with high surface smoothness is thought to increase the degree of freedom of the photographic material between the roller nips, but if both of the pair of rollers are made with highly slippery rollers, it becomes difficult to convey the photographic material. Become. Also,
The high slipperiness of the rollers increases the degree of freedom of the photographic material between the roller nips, reducing the transport speed of the photographic material and creating a gap in the transport speed with the rollers 3. Therefore, the relative rotational speed of the squeeze roller (the distance that a predetermined position on the roller surface moves per unit time) is made larger than that of the roller 3. By doing this, roller pair 4
Tension is applied to the photographic material between a, 4b and the pair of rollers 3, so that it can be conveyed without meandering.
In the example shown in FIG. 1, a driving roller 4b having a diameter larger than that of the roller 3 provided on the photographic material supply side with respect to the squeeze roller pair is used, but rollers 3, 4a and 4b have the same diameter. In some cases, the number of rotations per unit time of the pair of rollers 4a and 4b, one of which uses a roller with high surface smoothness, may be configured to be greater than that of the roller 3. Further, the diameters of both the rollers 4a and 4b may be larger than the diameter of the roller 3. Roller pair 4a, 4
The difference between the relative rotational speed between b and roller pair 3 does not need to be significantly large; for example, in the case of a roller with a diameter of about 2 to 5 cm, a difference of several mm is sufficient, and it depends on the slipperiness of roller 4b, etc. .

The rollers 4a and 4b shown in FIG. 1 can also be turned upside down; in this case, it is preferable to convey the photographic material with its photosensitive surface facing downward.

Furthermore, if necessary, at least one of the one or more pairs of guides or transport rollers provided in the photographic processing tank may be configured as described above. If the length of the photographic processing tank is short and wrinkles do not occur due to meandering even when processing a long photographic material, the following photographic processing tanks, such as neutralization tank, fixer tank, washing tank, plate-making processing The roller pair of at least one tank, such as a liquid bath (for example a desensitizing liquid bath), may be configured as described above. Of course, the process may be carried out using a plurality of photographic tanks including a developer tank.

When a desired pair of conveying rollers is configured as described above, the pairs of conveying rollers subsequent to the pair of rollers are also configured as pairs of rollers described above so that the photographic material is conveyed smoothly.

(E) Example In FIG. 1, a photo processing apparatus was used in which a rubber roller with a diameter of 30 mm was used as roller 4a, a phenol resin roller with a diameter of 32 mm was used as roller 4b, and rollers 3 and 5 were made exactly the same as roller 4a. A lithographic printing plate 2 using a silver complex diffusion transfer method exposed to helium-neon laser light was developed from a cassette 1 through a pair of carry-in rollers 3. (However, although the subsequent neutralization tank and drying part are not shown, the pair of conveyor rollers in this part are also rollers 4a and 4b.
). This printing plate uses polyethylene resin-coated paper as a support and has a width of 310 mm. The length of the developing tank is approximately 300 mm.

As a result of continuously processing all 225 m of printing plates in cassette 1, no wrinkles were observed.

For comparison, when a conventional photographic processing apparatus, which was the same as the apparatus shown in FIG. 1 except that roller 4b was replaced with roller 4a, was used, significant wrinkles appeared after about 4 m of photographic material was taken out from the pair of squeeze rollers. .

(F) Effects of the Invention By using the photographic processing apparatus of the present invention, it is possible to prevent the occurrence of wrinkles due to meandering even when processing a long photographic material.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of essential parts showing an example of a photographic processing apparatus of the present invention. 1... Cassette, 2... Photographic material, 3... Carrying roller pair, 4a... Rubber roller, 4b... Resin roller.

Claims (1)

[Claims] 1. A photoprocessing apparatus having at least one photographic processing tank and a plurality of pairs of conveying rollers for photographic materials, in which one roller has at least one pair of conveying rollers whose surface has greater slipperiness than the other roller, and A photographic processing apparatus characterized in that the relative rotational speed of the pair of rollers is configured to be greater than that of the pair of transport rollers on the photographic material supply side of the pair of rollers.