Patent Application
20110240790
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2010-078976 filed on Mar. 30, 2010, of which the contents are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a web winding method for winding a plurality of cut webs into a roll shape while being pressed by rider rollers.
2. Description of the Related Art
Recently, in a method for winding a cut web, taking as an example a surface winding method, a winding core is retained by two long surface drums (drive rollers), and a single rider roller, which is of the same length as the surface drums. While being gripped between the surface drums and the rider roller, when a rotary drive force is applied thereto, a plurality of small-width webs, which are cut by a cutting process and fed, are wound on the winding core. (See, Japanese Laid-Open Patent Publication No. 62-116448.)
In general, a wide raw fabric web has a thickness (thickness variation) that differs in the widthwise direction. For example, per 100 mm in a widthwise direction, a difference in thickness exists on the order of several μm. When a raw fabric web having such thickness variations in the widthwise direction is cut and each of webs, which are small in width, are wound simultaneously, the difference in thickness accumulates, and a variance in the winding diameters of respective webs occurs.
During winding of the webs, in the case that the winding diameters are different between plural webs as noted above, a difference occurs in the pressing force on each of the webs imposed from the surface drums and the rider roller, and as a result, differences can occur in the winding stiffness among each of the webs. In the event that differences in the pressing force are especially large, problems occur in that wrinkles may result in webs for which the winding stiffness is excessively strong, or winding looseness may occur in webs for which the winding stiffness thereof is insufficient.
Consequently, conventionally, the rider roller is divided into a plurality of divided rider rollers, the widthwise dimensions of which are smaller than the width of the cut webs. The respective divided rider rollers are sequentially arranged roughly coaxially at a given gap pitch, which is less than the width of each of the webs, each of the divided rider rollers being moved mutually independently in the pressing direction, whereby the respective webs are pressed thereby (see, for example, Japanese Patent No. 2678826 and Japanese Patent No. 3539786). Owing thereto, because the pressing force of the divided rider rollers with respect to each of the webs is averaged, differences in winding stiffness between respective webs does not occur. Accordingly, even if differences in the winding diameters between each of the webs occur, fear of wrinkles or poor performance due to excessive winding stiffness in a portion of the webs, or winding looseness caused by insufficient winding stiffness, can be eliminated.
Further, as a method for winding a material used for inkjet recording, there is known a method as disclosed in Japanese Laid-Open Patent Publication No. 2002-265106. With this method, the pressing force of a rider roller is regulated so as to reside within a range of from 5 to 40 kg per each one meter web width of the inkjet recording material. In this case, the inkjet recording material can be wound without decreasing the gloss (luster) of the inkjet recording material.
In the methods of Japanese Patent No. 2678826 and Japanese Patent No. 3539786, from the fact that a plurality of divided rider rollers are arranged with respect to a single web, when directed to winding of an inkjet recording material for example, if the pressing force of the divided rider rollers simply is increased, within the surface of the web, recesses occur at portions where the divided rider rollers press against the web, and boundaries (planar unevenness) with portions that are not pressed occur, which can be recognized by the naked eye. In such a case, the appearance thereof becomes unsatisfactory and the web cannot serve as a product.
Further, in the method of Japanese Laid-Open Patent Publication No. 2002-265106, and similarly in the disclosure of Japanese Laid-Open Patent Publication No. 62-116448, because winding is carried out while the webs are pressed by a single rider roller, when there are thickness variations in the widthwise direction of the raw fabric web, there are problems in that wrinkles in the web or looseness in the web windings tend to occur. In particular, there are further problems in that, at both ends of the web, winding portions become gradually expanded out toward the center, and shifting between the windings (telescopic winding) is generated.
Consequently, although it might be considered as a way of resolving the aforementioned problems to apply the divided rider rollers of Japanese Patent No. 2678826 and Japanese Patent No. 3539786 to the method of Japanese Laid-Open Patent Publication No. 2002-265106, because a large number of divided rider rollers are arranged, due to the fact that the width of the individual divided rider rollers becomes smaller, the pressing force produced thereby increases, and planar unevenness occurs. Further, if the pressing force is decreased in order to avoid such planar unevenness, there is a problem in that shifting between the windings easily occurs. Additionally, because the region of stability (stable operating region) thereof is narrow, there is a concern that manufacturability is decreased.
The present invention has been devised taking into consideration the foregoing types of problems, and has the object of providing a web winding method in which, even if there is unevenness in thickness in a widthwise direction of the raw fabric web, wrinkles, winding looseness, shifting in the windings and planar unevenness, etc., do not occur, and deterioration in manufacturability can be suppressed.
According to the present invention, a web winding method is provided for winding a plurality of cut webs in a rolled form while applying pressure thereto by rider rollers, wherein among a web grouping, which is constructed by aligning the plurality of webs in a sideways direction, at least with respect to webs that are positioned at opposite ends of the web grouping, two or more first divided rider rollers are disposed in a widthwise direction of each of the webs, and together therewith, respective individual second divided rider rollers are disposed with respect to webs apart from the webs positioned at the opposite ends, and the plurality of webs is wound.
In the present invention, a width of the first divided rider rollers is 15 to 200 mm, and a pressing force of the first divided rider rollers is 0.5 to 6 kgf per each roller.
In the present invention, the first divided rider rollers and the second divided rider rollers have a rubber hardness degree of 30° to 50°.
In the present invention, divided rider rollers on which a rounding chamfering process is implemented on end surfaces thereof are used at least as the first divided rider rollers.
In the present invention, among the web grouping, a pressing force per meter in a widthwise direction by one or more of the first divided rider rollers, which is arranged corresponding to a first portion across a widthwise center from a left end of a left end web, and among the web grouping, a pressing force per meter in a widthwise direction by one or more of the first divided rider rollers, which is arranged corresponding to a first portion across a widthwise center from a right end of a right end web, are 30 kgf/m or less respectively upon winding of the plurality of webs.
In the present invention, within the left end web, a pressing force per meter in a widthwise direction at one or more of the first divided rider rollers, which is arranged corresponding to a second portion apart from the first portion, and within the right end web, a pressing force per meter in a widthwise direction at one or more of the first divided rider rollers, which is arranged corresponding to a second portion apart from the first portion, are 30 kgf/m or less upon winding of the plurality of webs.
In the present invention, the webs comprise an inkjet recording material.
In accordance with the web winding method of the present invention, as described above, even if there is unevenness in thickness in a widthwise direction of the raw fabric web, wrinkles, winding looseness, shifting in the windings and planar unevenness, etc., do not occur, and deterioration in manufacturability can be suppressed.
The above and other objects features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention are shown by way of illustrative example.
An embodiment to which the winding method according to the present invention, for example, a surface winding method, is applied shall be described below with reference to
To carry out the web winding method according to the present embodiment, surface winding equipment 10 is used in which a cutting apparatus 12 and a winding apparatus 14 are combined.
The cutting apparatus 12 includes a plurality of cutters 16 arranged in one direction, which cut a wide web (raw fabric web 18) that is fed out from an unillustrated raw fabric roll into a plurality of narrow webs 20.
The raw fabric web 18 and the webs 20 are recording sheets used for inkjet printing, comprising a supporting material body, and an ink accommodating layer containing inorganic particles and a water-soluble metallic compound disposed on the supporting material body.
The inorganic particles may be made up, for example, from particulate silica, colloidal silica, titanium dioxide, barium sulfate, calcium silicate, zeolite, kaolinite, halloysite, mica, talc, calcium carbonate, magnesium carbonate, calcium sulfate, pseudo-boehmite, zinc oxide, zinc hydroxide, alumina, aluminum silicate, calcium silicate, magnesium silicate, zirconium oxide, zirconium hydroxide, cerium oxide, lanthanum oxide, yttrium oxide, and the like. Among such materials, from the standpoint of being formed with a favorable porous structure, particulate silica, colloidal silica, alumina or pseudo-boehmite are preferred.
As the water-soluble metallic compound, there may be used a metallic water soluble salt selected, for example, from calcium, barium, manganese, copper, cobalt, nickel, aluminum, iron, zinc, zirconium, chrome, tungsten and molybdenum.
From a standpoint of improving the gloss (luster) of the ink accommodating layer, among the ink accommodating layers that are disposed on the supporting material body, the uppermost layer, which is separated farthest from the supporting material body, preferably contains colloidal silica. Below, the uppermost layer containing colloidal silica therein shall be referred to as a “colloidal silica layer.”
The layer thickness of the ink containing layer is preferably 10-50 μm, and more preferably, 20-40 μm. The layer thickness of the colloidal silica layer, from the standpoint of ink absorption and gloss, is preferably 0.05-5 μm, and more preferably, 0.1-3 μm.
The winding apparatus 14 shown in
The driving system made up of the respective divided rider rollers 24 may have a similar structure to that disclosed in Japanese Patent No. 2678826 and Japanese Patent No. 3539786. As shown in
The width of the first divided rider roller 24a is 15-200 mm. Respective widths of the plurality of first divided rider rollers 24a that are arranged on the left end web 20a may be the same or of different widths. For example, as shown in
As an example of arranging the first divided rider rollers 24a, one of the first divided rider rollers having a width of 200 mm is arranged corresponding to the first portion 40a of the left end web 20a having a width in excess of 400 mm, whereas in the same manner, one of the first divided rider rollers 24a having a width of 200 mm is arranged on the second portion 40b. In this case, a total of two first divided rider rollers 24a are disposed with respect to the left end web 20a.
As other examples, two of the first divided rider rollers 24a having a width of 100 mm may be arranged corresponding to the first portion 40a, whereas one of the first divided rider rollers 24a having a width of 200 mm may be arranged on the second portion 40b, or alternatively, a first divided rider roller 24a having a width of 150 mm and a first divided rider roller 24a having a width of 50 mm may be arranged corresponding to the first portion 40a, whereas one first divided rider roller 24a having a width of 200 mm may be arranged on the second portion 40b. Naturally, a plurality of first divided rider rollers 24a may also be arranged on the second portion 40b.
Additionally, as shown in
Moreover, in the present embodiment, the plurality of webs 20 are wound under a condition in which the pressing force from the first divided rider rollers 24a is 0.5-6 kgf per each roller, while the pressing force per unit length in the widthwise direction at the divided rider rollers 24 is kept constant.
Consequently, even if there are thickness irregularities in the widthwise direction of the raw fabric web 18, the occurrence of wrinkles, winding looseness, shifting in the windings, and planar unevenness can be suppressed.
The divided rider rollers 24 preferably have a rubber hardness degree of 30° to 50°. If the rubber hardness degree is too low, the divided rider rollers 24 contact the webs 20 too closely and the coefficient of dynamic friction increases, leading to a concern that rotary movement of the webs 20 will be obstructed. In contrast, if the rubber hardness degree is too high, then there is a concern that the webs may become deformed and decrease in luster, and planar unevenness may occur.
Further, preferably, a rounding chamfering process is implemented on end surfaces of the divided rider rollers 24. In this case, the radius of the rounded surface is 2 mm or greater. Owing thereto, the occurrence of planar unevenness can be suppressed. The upper limit of the radius of the rounded surface depends on the width of the divided rider rollers 24, for example, if the width is 15 mm the radius is 3 mm, if the width is 20-50 mm the radius is 4 mm, if the width is 60-100 mm the radius is 5 mm, if the width is 110-150 mm the radius is 6 mm, and if the width is 160-200 mm the radius is 7 mm.
Below, the present invention shall be described in greater detail with reference to preferred embodiments of the present invention. Materials, usage amounts, percentages, process contents, process steps and the like, which are indicated in the embodiments below, can be suitably modified without deviating from the essential gist of the present invention. Accordingly, the scope of the present invention should not be interpreted as being limited by the specific examples described below.
The condition of occurrence of wrinkles, winding looseness, shifting in windings, and planar unevenness was confirmed in relation to the present embodiment as well as comparative examples 1 through 3.
An ink accommodating layer was coated and dried on a 650 mm wide, 230 μm thick support body, and as shown in
In particular, in the present embodiment, as shown in
The width of the first divided rider rollers 24a was set at 65 mm. At the left end web 20a, the left end of one individual first divided rider roller 24a was arranged at a point 5 mm from the left end thereof, while the left end of the second individual first divided rider roller 24a was arranged at a point 10 mm from the right end of the one first divided rider roller 24a. Similarly, at the right end web 20b, the right end of the one individual first divided rider roller 24a was arranged at a point 5 mm from the right end thereof, while the right end of the second individual first divided rider roller 24a was arranged at a point 10 mm from the left end of the one first divided rider roller 24a.
The width of the second divided rider rollers 24b was set at 140 mm. The second divided rider rollers 24b were arranged such that, at each of the webs 20, both sides of the webs 20 protruded therefrom by roughly 5 mm.
The pressing force from each of the first divided rider rollers 24a was 1.5 kgf per each roller, and the pressing force per unit meter by each of the first divided rider rollers 24a was 23 kgf/m. The pressing force from each of the second divided rider rollers 24b was 3 kgf per each roller, and the pressing force per unit meter by each of the second divided rider rollers 24b was 21 kgf/m.
As shown in
As shown in
The width of each of the divided rider rollers 24 was set at 25 mm. In addition, at each of the webs, the left end of the first divided rider roller 24 was positioned at a point 5 mm from the left end of each of the webs 20, while the right end of the fourth divided rider roller 24 was positioned at a point 5 mm from the right end of each of the webs 20, and gaps of 10 mm were disposed respectively between each of the divided rider rollers 24.
As shown in
Evaluation
Among the four rolls 28, following winding thereof, the left end roll 28a on which the left end web 20a was wound and the right end roll 28b on which the right end web 20b was wound were extracted, and it was confirmed respectively using the naked eye whether or not winding looseness had occurred in the left end roll 28a and the right end roll 28b, whether or not wrinkles and planar unevenness had occurred in each of the surfaces thereof, and further, whether or not shifting in the windings had occurred respectively at the left end of the left end roll 28a and at the right end of the right end roll 28b.
Evaluation Results
In the first comparative example, there was winding looseness in the left end roll 28a and in the right end roll 28b, and it was understood that the winding condition was unsuitable. Further, in each of the surfaces, wrinkles occurred caused by winding looseness. Planar unevenness due to use of the divided rider rollers 24 was not confirmed.
In the second comparative example, although winding looseness was not exhibited in the left end roll 28a and the right end roll 28b, planar unevenness occurred in each of the surfaces. From the fact that pressure was applied with respect to each of the webs 20 by the divided rider rollers 24 each having a width of 25 mm, it can be considered that the surface pressure was strongly increased, and planar unevenness occurred to a degree discernable by the naked eye. Shifting in the windings was not confirmed.
In the third comparative example, winding looseness did not occur in the left end roll 28a and the right end roll 28b, and neither wrinkles nor planar unevenness was confirmed. However, it was confirmed that shifting in the windings on the order of 1 mm and greater had occurred.
In the present embodiment, winding looseness did not occur in the left end roll 28a and the right end roll 28b, and wrinkles and planar unevenness in each of the surfaces was not confirmed. Further, shifting in the windings was not confirmed.
Next, winding of webs 20 was carried out using the same method as in the aforementioned first embodiment, and the relationship between widths of the first divided rider rollers 24a corresponding to the first portions 40a, the pressing force per each roller, the pressing force per meter in the width direction caused thereby, and the occurrence of planar unevenness and shifting in the windings was confirmed. The results of this study are shown in
In
Evaluation
It was understood that planar unevenness was generated at a stage in which the pressing force per meter exceeded 30 kgf/m. Accordingly, it was understood that the number and the pressing force per each roller should be determined within a range in which the pressing force per meter of the first divided rider rollers 24a arranged at the first portions 40a is 30 kgf/m or less.
Herein, when examples are shown of arranging the first divided rider rollers 24a with respect to the first portions 40a having a width, for example, in excess of 200 mm, the following conditions result.
(a) An individual first divided rider roller 24a having a width of 200 mm is arranged (as discussed above). In this case, the pressing force per each individual roller can be selected arbitrarily from within a range of 0.5-6 kgf per each roller.
(b) Two first divided rider rollers 24a having a width of 100 mm are arranged (as discussed above). In this case, the pressing force per each individual roller can be selected arbitrarily from within a range of 0.5-3 kgf per each roller.
(c) An individual first divided rider roller 24a having a width of 150 mm is arranged. In this case, the pressing force per each individual roller can be selected arbitrarily from within a range of 0.5-4.5 kgf per each roller.
(d) One first divided rider roller 24a having a width of 150 mm and one first divided rider roller 24a having a width of 50 mm are arranged. In this case, the pressing force per each individual roller can be selected from within a range of 0.5-4.5 kgf for the first divided rider roller 24a having a width of 150 mm, and within a range of 0.5-1.5 kgf for the first divided rider roller 24a having a width of 50 mm, and from combinations thereof such that the pressing force per meter by the two first divided rider rollers 24a becomes 30 kgf/m.
(e) One first divided rider roller 24a having a width of 100 mm and two first divided rider rollers 24a having a width of 50 mm are arranged. In this case, the pressing force per each individual roller can be selected from within a range of 0.5-3.0 kgf for the first divided rider roller 24a having a width of 100 mm, and within a range of 0.5-1.5 kgf for the first divided rider rollers 24a having a width of 50 mm, and from combinations thereof such that the pressing force per meter by the three first divided rider rollers 24a becomes 30 kgf/m.
The aforementioned conditions (a) through (e) are shown as examples only. It is a matter of course that various other combinations apart therefrom could be considered.
From the second embodiment, it was understood that if the width of the first divided rider rollers 24a is 15-200 mm while the pressing force of the first divided rider rollers 24a is 0.5-6 kgf per each roller, then in the left end web 20a and the right end web 20b, the occurrence of wrinkles, winding looseness, shifting in the windings and planar unevenness can be suppressed. In addition, by setting the pressing force per meter produced by the one or more first divided rider rollers 24a, which are arranged corresponding to the first portions 40a, to be 30 kgf/m, the occurrence of wrinkles, winding looseness, shifting in the windings and planar unevenness can be further suppressed.
Further, concerning the first divided rider rollers 24a that are arranged corresponding to the second portions 40b as well, by setting the width thereof to 15-200 mm, the pressing force per each roller to 0.5-6 kgf per each roller, and the pressing force per meter produced by the one or more first divided rider rollers 24a, which are arranged corresponding to the second portions 40b, to be 30 kgf/m, through cooperation with the first divided rider rollers 24a that are arranged corresponding to the first portions 40a, the occurrence of wrinkles, winding looseness, shifting in the windings and planar unevenness can be even further suppressed.
Concerning the second divided rider rollers 24b that are arranged corresponding to webs 20 apart from the left end web 20a and the right end web 20b as well, preferably the width thereof is set to 15-200 mm, while the pressing force per each roller is set to 0.5-6 kgf per each roller.
Although certain preferred embodiments of the web winding method according to the present invention have been shown and described in detail, it should be understood that the invention is not limited to the above-described embodiments. It is a matter of course that various modified or additional structures could be adopted therein without deviating from the essence and gist of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2010-078976 | Mar 2010 | JP | national |
