A cleaning tape for photographic material transporting rollers

Abstract: A cleaning tape for use in cleaning transporting surfaces of transporting rollers arranged along a photographic material transporting passageway, comprises a tape body (3) provided on at least one side thereof with an adhesive layer (4, 40), with a distance away from one lengthwise end thereof; and a porous screen (5) laid on the adhesive layer.

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a cleaning tape for use in cleaning photographic material transporting rollers in a photographic processor. Description of the Prior Art In general, a number of paired transporting rollers, composed of drive side transporting rollers and driven side transporting rollers press-contacted with the drive side transporting rollers, are arranged along a transporting passageway of a negative film or a photographic (printing) paper in the photographic processor so that the negative film or photographic paper can be transported along the transporting passageway. In this photographic processor, when the transporting rollers are contaminated by contaminants, such as dirt, built up thereon, the transporting rollers are slipped against the photographic material. As a result, the transport of the photographic material cannot be performed with accuracy. For avoidance of this problem, various cleaning methods are proposed. One typical cleaning of prior methods is that the transporting rollers in the photographic processor are cleaned out with a separately prepared waste. This cleaning way is however poor in workability in its requiring that after operation of the photographic processor is stopped, the transporting rollers in the photographic processor be cleaned out manually from a handhole of the processor. There is proposed another cleaning way that a tape having on one side surface thereof a liquid absorbing layer of a non-woven fabric impregnated with a solvent such as acetone or alcohol is passed through the pairs of transporting rollers to clean out the contaminants on the transporting rollers by means of the liquid absorbing layer impregnated with the solvent. This cleaning way however sometimes causes problems that sensors are contaminated by the solvent with which the liquid absorbing layer is impregnated and that working environment becomes worse by evaporation of the solvent. There is proposed still another cleaning way that a tape simply having on one side surface thereof an adhesive layer is passed through the pairs of transporting rollers to transfer the contaminants on the transporting rollers to the adhesive layer. This cleaning way however involves problems that the adhesive layer sometimes adhere to not only the transporting rollers but also another parts accidentally, so that the tape is captured by them. As a result of this, the smooth cleaning is hindered to inevitably produce reduced efficiency of the cleaning. SUMMARY OF THE INVENTION In the light of these circumstances, the present invention has been made. It is the object of the invention to provide a cleaning tape capable of reliably cleaning out contaminants on the transporting rollers of the photographic processor with efficiency and without being rolled into the transporting rollers. According to the present invention, there is provided a cleaning tape adapted for cleaning the transporting surfaces of transporting rollers (2a, 2b) arranged along a photographic material transporting passageway, characterized in that the cleaning tape comprises a tape body of a predetermined length, a layer of adhesive provided on a lengthwise center portion (C) of one of the sides of the body, and a porous screen which is bonded on the adhesive layer, the two end portions of the tape body remaining uncovered by the adhesive and the porous screen and in that, when the surface of the portion (C) of the tape body on which is provided the adhesive layer is in a non-pressurized state, the porous screen protrudes from the surface of the adhesive layer so that the cleaning tape can show substantially non-tackiness, while on the other hand, when the surface of the portion (C) of the tape body on which is provided the adhesive layer is in a pressurized state, the adhesive layer is emerged from porous portions of the porous screen so that the cleaning tape can show substantially tackiness. It is preferable that an entire length of the adhesive layer is set to such a length that the transporting rollers can turn not less than one turn. Further, it is preferable that a ratio (S1 / S2) of an area S1 of exposed surfaces of the adhesive layer emerged from the porous screen and an area S2 of part of the adhesive layer on which the porous screen is provided is in the range of from 50/1 to 1/10. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view of a photographic processor; FIG. 2 is a schematic showing of a part of the photographic processor; FIG. 3 is a schematic plan view of a cleaning tape according to the invention; FIG. 4 is a schematic front view of the same; FIG. 5 is an enlarged view of the part of the same; FIG. 6 is an enlarged sectional view of the same; FIG. 7 is an enlarged sectional view of a part of the cleaning tape in the state of being pressurized by paired transporting rollers; FIG. 8 is an enlarged plan view of a part of a cleaning tape of another embodiment; FIG. 9 is an enlarged sectional view of a part of a cleaning tape of another embodiment; and FIG. 10 is a schematic front view of a cleaning tape of still another embodiment. DETAILED DESCRIPTION OF THE EMBODIMENT Referring now to the accompanying drawings, examples of the preferred embodiments of the present invention directed to a cleaning tape for photographic material transporting rollers will be described below. It is to be understood, however, that the scope of the invention is by no means limited to the illustrated embodiments. FIG. 1 is a schematic showing of a photographic processor for use with the cleaning tape of the present invention. The photographic processor has a known structure, basically comprising a negative film feeding device 1a, an exposure device 1c for printing negative film images on a printing paper drawn out of a paper magazine 1b, a processor 1d for processing the printing paper exposed by the exposure device 1c, a drying device 1e for drying the processed printing paper, a print discharging device 1f for cutting the dried printing paper at predetermined lengths and discharging the as-cut printing papers as prints, and a negative film discharging device 1g for cutting the negative film used in the exposure device 1c and discharging the as-cut negative films. In the photographic processor, a number of paired transporting rollers 2, composed of drive side transporting rollers 2a and driven side transporting rollers 2b press-contacted with the drive side transporting rollers 2a, are spaced at a predetermined interval along a negative film transporting passageway 10 extending from the negative film feeding device 1a through the exposure device 1c to the print discharging device 1f, as schematically shown in FIG. 2, so that the negative film can be transported along the transporting passageway 10 via the paired transporting rollers 2. In the photographic processor, an intermediate insertion portion 11 from which a piece of developed film and the like is fed to a midpoint of the negative film transporting passageway 10 is arranged at the midpoint in the negative film transporting passageway 10 at the upstream side of the exposure device 1c. Also, a number of transporting rollers (not shown) are arranged along a photographic (printing) paper transporting passageway 12 extending from the paper magazine 1b through the exposure device 1c to the processor 1d. Now, the preferred embodiments of the present invention directed to a cleaning tape for use in cleaning transporting surfaces of the paired transporting rollers 2 assembled in the photographic processor described above will be detailed below. Shown in FIGS. 3 to 7 is a cleaning tape designed especially for cleaning the transporting rollers 2a, 2b arranged along the negative film transporting passageway 10 mentioned above. The cleaning tape basically comprises a tape body 3 having a predetermined length. The tape body 3 is formed from polyethylene terephthalate, having a thickness of 125 µm, a width of about 35mm, an entire length of about 390mm and having such elasticity in bending that it can be restored nearly perfectly to its original flat form against the bending under use. The tape body 3 may be formed from a plastic sheet of, for example, polypropylene or vinyl chloride, in addition to polyethylene terephthalate, a sheet of paper (a resin-impregnated paper, in particular), a sheet of synthetic paper, or laminated sheets thereof. Though no particular limitation is imposed on the thickness of the sheet, the sheet usually have a thickness of the order of 12 µm to 2mm, preferably the order of 50 µm to 1.0mm in consideration of hardness or equivalent for workability. Adhesive layers 4, 40 of 25 µm in thickness (in thickness after coated and dried) are applied on front and rear surfaces of a tape-like sheet 30 of 75 µm in thickness, about 35mm in width and about 290mm in entire length. A porous screen 5 is laid on the adhesive layer 4 at the front side of the sheet. The sheet 30 adheres on one side of the tape body 3 at a lengthwise center part thereof through the adhesive layer 40, without providing the adhesive layer 4 at both lengthwise end portions of the tape body 3. The both end portions of the tape body 3 in which the adhesive layer 4 is not located are formed as roll-in preventing portions 6 for preventing the tape body 3 from being rolled into the transporting rollers 2a, 2b by the adhesion of the adhesive layer 4. Also, the portion of the tape body 3 on which the sheet 30 adheres is formed as a cleaning portion C. An adhesive of the adhesive layers 4, 40 used is made by 90 parts by weight of 2-ethylhexyl acrylate, 10 parts by weight of acrylic acid and 300 parts by weight of ethyl acetate being mixed and copolymerized. The materials which may be used for adhesive layers 4, 40 include synthetic rubbers including acrylic rubbers, styrene rubbers and silicon rubbers and natural rubbers, in addition to the one mentioned above. The adhesive layers should preferably have a thickness smaller than the porous screen 5 as described later by the order of 10-50%. With an excessively large thickness of the adhesive layer 4, there is a fear of an overflow of the adhesive over the porous screen 5. In the illustrated embodiment, the entire length of the adhesive layer 4 is set to such a length that the transporting rollers 2a, 2b can turn about 4 turns. The porous screen 5 is made using a rough knitted fabric into which polyester fibers of 45 µm in thickness is knitted by plain knitting, as shown in FIG. 5. The porous screen 5 is adhesive bonded on the adhesive layer 4 by pressing with an iron roll with the temperature of 130°C. A ratio S1/S2 of an area S1 of the exposed surfaces 4a of the adhesive layer emerged from the porous screen 5 of the cleaning tape and an area S2 of part of the adhesive layer on which the porous screen 5 is adhesive bonded is set to be 3.8/1. It is to be noted that the ratio S1/S2 of the area S1 of the exposed surfaces 4a of the adhesive layer and the area S2 of the part of the adhesive layer on which the porous screen 5 is adhesive bonded should be in the range of from 50/1 to 1/10, preferably from 20/1 to 1/5, further preferably from 10/1 to 1/3. With the ratio S1/S2 of more than 50, it is hard to ensure substantial tackiness in the non-pressurized state, as will be discussed later, while on the other hand, with the ratio of less than 1/10, it is hard for the tackiness to develop in the pressurized state, as will be discussed later. From the viewpoint that the elasticity in the thicknesswise direction is produced particularly by intersecting parts of the fibers, it is preferable that the porous screen 5 is formed by the knitted fabric as shown in FIG. 5. The materials which may be used for the porous screen include polypropylene, Tetron and mixtures thereof, in addition to the polyester fibers mentioned above. In place of the knitted fabric by plain knitting as mentioned above, a woven fabric by plain weave as shown in FIG. 8, a non-woven fabric, paper, or a plastic net may be used for the porous screen 5. With this constructed cleaning tape, when the transporting surfaces of the transporting rollers 2a or 2b contact with the porous screen 5, for example, if the contact pressure is substantially zero, the porous screen 5 protruding from the surface of the adhesive layer 4 allows the transporting rollers 2a or 2b to be prevented from contacting with the exposed surfaces 4a of the adhesive layer. The cleaning tape will then show substantially non-tackiness. It is noted here that the expression of "substantially non-tackiness" means the tackiness of such a level that when a man lightly contacts with the cleaning tape with his finger, he won't feel any tack. On the other hand, when the transporting surfaces of the transporting rollers 2a, 2b contact with the porous screen 5 with an adequately large contact pressure, the surface of the cleaning tape is put in the pressurized state, as shown in FIG. 7. The deformation of the cleaning tape causes adhesive layer 4 to be emerged from the porous portions of the porous screen 5. As a result of this, the exposed surface 4a of the adhesive layer comes to be substantially flush with the surface of the porous screen 5 and thus comes to contact with the transporting surfaces of the transporting rollers 2a or 2b, and the cleaning tape is then allowed to develop its tackiness. With an excessively strong tackiness of the cleaning tape, there is a fear that the transporting surfaces of the transporting rollers 2a, 2b may be scratched by the cleaning tape or the adhesives may be transferred to the transporting rollers. Because of this, the tackiness of the cleaning tape is usually of not more than 5kg/20mm, preferably the order of 2kg/20mm to 200g/20mm. In the illustrated embodiment, the tackiness of the cleaning tape is of 850g /20mm. It should be noted that the values of "tackiness" presented herein indicates the values obtained when the cleaning tape having no porous screen 5 is adhesive bonded to a stainless plate by making one reciprocating motion of a roller with a load of 2kg and shortly thereafter is peeled away therefrom 180° at the speed of 300mm/min. When the transporting rollers 2a, 2b arranged along the negative film transporting passageway 10 in the photographic processor are cleaned by use of the cleaning tape, the roll-in preventing portion 6 provided at one lengthwise end of the cleaning tape is first inserted in the intermediate insertion portion 11 provided at a midpoint of the transporting passageway 10. In this stage, the cleaning tape is in the non-pressurized state and thus is of substantially non-tackiness. As a result of this, the cleaning tape can be smoothly inserted without adhering to the insertion portion 11. Then, the inserted cleaning tape is held in sandwich relation and in the pressurized state between the transporting rollers 2a, 2b at the roll-in preventing portion 6 of the tape body 3, as schematically shown in FIG. 4, and is fed downstream from the transporting rollers 2a, 2b. The tape body 3 has such elasticity in bending as to be substantially completely restored to its original flat form against the bending and, besides, the roll-in preventing portion 6 of the tape body has no adhesive layer 4, thus allowing the roll-in preventing portion 6 to be prevented from adhering to the transporting surfaces of the transporting rollers 2a, 2b. In other words, the cleaning tape is prevented from adhering to and being rolled in the transporting rollers 2a, 2b. As a result of this, the cleaning tape is smoothly fed downstream from the paired transporting rollers 2 to the next paired transporting rollers 2. When the cleaning tape is transported while it is held in sandwich relation between the transporting rollers 2a, 2b and in the pressurized state, the surface of the cleaning tape develops its tackiness after a portion of the tape body 3 in which the adhesive layer 4 and the porous screen 5 are provided is pressurized by the both rollers 2a, 2b. Also, the transporting rollers 2a, 2b formed of elastic material are deformed after that point. Thus, from after the transporting surfaces of the transporting rollers 2a or 2b contact with the exposed surfaces 4a of the adhesive layer until they separate therefrom, contaminants such as dirt adhering on the transporting surfaces are transferred to the exposed surfaces 4a of the adhesive layer. By virtue of this transferring effect, the transporting surfaces are cleaned out. In this case, when the exposed surface 4a of the adhesive layer and the transporting surfaces of the transporting rollers 2a or 2b are separated from each other, the exposed surfaces 4a are held at their peripheries against a tensile force acting on the interfaces therebetween by circumferences of meshes of the porous screen 5. As a result, a tensile stress acting on the tacky interface between the exposed surfaces 4a of the adhesive layer and the tape body 3 is reduced to that amount. As a result of this, the exposed surfaces 4a of the adhesive layer can well be prevented from being separated from the tape body 3 and transferred to the transporting rollers 2a or 2b (the so-called "transference of adhesives"). When the cleaning tape is released from pressurization by the paired transporting rollers 2, the tape body 3, the adhesive layer 4 and the porous screen 5 are restored to their original forms. Then, the porous screen 5 protrudes from the exposed surfaces 4a of the adhesive layer again and comes to be substantially non-tackiness again. As a result of this, even when the cleaning tape contacts with the guide member or something within the transporting passageway 10, the tape is prevented from adhering to the guide member or something. It is to be understood that the invention is not limited to the illustrated embodiment in which the adhesive layers 4, 40 are formed on the front and rear surfaces of the tape-like sheet 30, respectively, and the porous screen 5 is laid on the adhesive layer 4 at the front side of the sheet so that the sheet 30 can be allowed to adhere on one side of the tape body 3 through the adhesive layer 40. For example, the invention may be modified such that the adhesive layer 4 is formed directly on the front surface of the tape body 3 and the porous screen 5 is laid on the surface of the adhesive layer 4, as shown in FIG. 9. Also, the cleaning portion C composed of the adhesive layer 4 and the porous screen 5, which in illustration is formed on one side of the tape body 3 only, may be formed on both sides of the tape body 3, as schematically shown in FIG. 10. This modification can provide the effect of cleaning out the transporting rollers 2a, 2b of each pair of the paired transporting rollers 2 simultaneously. The roll-in preventing portion 6, which in illustration is arranged at both lengthwise end portions of the tape body 3, may be arranged only at one lengthwise end portion of the tape body 3. Synthetic rubber adhesives (in which 150 parts by weight of tackifier (MARUKAREZ H700M available from Maruzen Petrochemical Co., Ltd.) is mixed, with a solids content of 100 parts by weight, in 50 weight % of toluene solution of styrene-isoprene-styrene polymers (KRATON 1107 available from Shell Chemical Co., Ltd.), and further 3 parts by weight of aging prevention agent is added to the mixture) may be used as an adhesive for forming the adhesive layer 4. ADVANTAGE OF THE INVENTION As discussed above, according to the cleaning tape of the invention, the tape body is provided on at least one side thereof with the adhesive layer, with a distance away from one lengthwise end thereof, and the porous screen is laid on the adhesive layer. This can produce the effect that contaminants of the transporting rollers of the photographic processor can reliably be cleaned out with efficiency and without being rolled into the transporting rollers. Also, according to cleaning tape of the invention, when a portion of the tape body forming thereon the adhesive layer is in the non-pressurized state, the tape body shows substantially non-tackiness, and the tackiness does not develop until the portion of the tape body comes to be in the pressurized state. This can provide the following results. When the tape body passes through the paired transporting rollers, the transporting surfaces of the transporting rollers can be cleaned out with increased efficiency by an adequately strong tackiness of the tape body as pressurized by the paired transporting rollers. Besides, when the cleaning tape as passed through the paired transporting rollers is released from pressurization by the paired rollers, the portion of the tape body can be restored to its original substantial non-tackiness to allow the tape body to move smoothly. Therefore, the cleaning of the transporting rollers can be conducted without stopping the photographic processor, as a whole, to effect a very useful cleaning of the transporting rollers. In addition, according to the cleaning tape of the invention, the entire length of the adhesive layer is set to such a length that the transporting rollers can turn not less than one turn. This can produce the effect of reliable cleaning of the transporting rollers. Further, according to the cleaning tape of the invention, a ratio (S1/S2) of an area S1 of the exposed surfaces of the adhesive layer emerged from a porous portion of the porous screen and an area S2 of part of the adhesive layer on which the porous screen is provided is set to be in the range of from 50/1 to 1/10. This can produce the effect that the transporting rollers can be cleaned out with further improved efficiency.

Claims: A cleaning tape adapted for cleaning the transporting surfaces of transporting rollers (2a, 2b) arranged along a photographic material transporting passageway, characterized in that the cleaning tape comprises a tape body (3) of a predetermined length, a layer (4) of adhesive provided on a lengthwise center portion (C) of one of the sides of the body. and a porous screen (5) which is bonded on the adhesive layer, the two end portions (6) of the tape body remaining uncovered by the adhesive and the porous screen (3) and in that , when the surface of the portion (C) of the tape body (3) on which is provided the adhesive layer (4) is in a non-pressurized state, the porous screen (5) protrudes from the surface of the adhesive layer (4) so that the cleaning tape can show substantially non-tackiness, while on the other hand, when the surface of the portion (C) of the tape body (3) on which is provided the adhesive layer (4) is in a pressurized state, the adhesive layer (4) is emerged from porous portions of the porous screen (5) so that the cleaning tape can show substantially tackiness. A cleaning tape for use in cleaning photographic material transporting rollers according to claim I, wherein an entire length of the adhesive layer (4) is set to such a length that the transporting rollers (2a, 2b) can turn not less than one turn. A cleaning tape for use in cleaning photographic material transporting rollers according to claim 1 or claim 2, wherein the ratio (S1 / S2) of the area S1 of exposed surface of the adhesive layer (4) emerged from the porous screen and (5) the area S2 of the part of the adhesive layer (4) on which the porous screen (5) is provided is in the range of from 50 / 1 to 1 / 10.

Inventors: NARUKAMI SHINJI, TANAKA NAOMITSU, NARUKAMI, SHINJI, TANAKA, NAOMITSU
Applicants: NITTO DENKO CORP, NORITSU KOKI CO LTD, NITTO DENKO CORPORATION, NORITSU KOKI CO., LTD.
Application year: 1999
Main classification: G03D3
IPC codes: B65H27, G03D3, G03D13, B08B7