JP2009166498A - Fabric and printing blanket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fabric for preventing intrusion of a cleaning liquid from the side face and the bottom face of a blanket while securing adhesiveness to a blanket support layer when a printing blanket is cleaned, and the printing blanket using the fabric. <P>SOLUTION: The fabric of a printing blanket is made of a warp and a woof subjected to an oil repellency treatment, the amount of the woof appearing on one face of the fabric is 60% to 80% in terms of the area ratio shown by a fabric structural diagram, and the fabric comprises a surface printing layer and a support layer consisting of at least one layer. The printing blanket uses the fabric as at least one layer of the support layer, and in this case, preferably, the fabric is used as the bottom layer of the support layer and the one face having the amount of the woof of 60% to 80% in terms of the area ratio is used as the bottom face of the blanket. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a woven fabric as a surface printed layer support constituting a printing blanket and a printing blanket using the woven fabric.

  In the printing unit of the printing press, for example, as shown in FIG. 6, the screen of the plate cylinder is transferred to a blanket wound in close contact with the outer periphery of the blanket cylinder, and this is further transferred to a printing medium (paper or the like). It has become. This printing blanket that mediates the screen of the plate cylinder to the substrate to be printed is usually formed by a surface rubber layer (surface printing layer) composed of a rubber layer and a support layer that supports the surface rubber layer. Furthermore, it is composed of a plurality of layers, and each layer may be formed of a woven fabric or a non-woven fabric, or may be formed by adding a buffer layer such as a sponge layer to these woven fabric layers.

  By the way, as the woven fabric of the support layer, one that has been stretch-processed in the warp direction (residual elongation of 4% or less) is used in order to reduce the longitudinal feed elongation accompanying the rotation of the roll. As a result, the weft yarn that is in a wavy line around the warp is narrowed and contracted in the length direction as the warp is stretched, so the blanket is moved in the weft direction (lateral direction) by the subsequent printing pressure. It becomes easy to grow. Such a weft condition is likely to cause lateral movement of the rotating blanket surface rubber layer. In printing without high-speed rotation, since the lateral load applied to the surface rubber layer is small, there is little movement of the surface rubber layer in the lateral direction, and even if such movement of the surface rubber layer occurs, printing failure or Although paper separation failure is unlikely to occur, an increase in printing pressure accompanying an increase in printing speed leads to dot gain and paper separation failure due to the lateral movement of the surface rubber layer, particularly as shown in FIG. In the BB type printing using two blanket cylinders, the printing pressure is further increased to ensure transfer, and thus there is a tendency to increase printing defects and paper separation defects associated with the lateral movement.

  In addition, as an invention for preventing lateral movement of the surface rubber layer of the blanket, a high-density fabric having more warps than wefts is disclosed (for example, see Patent Document 1), but further improvement is required. It has been.

  Another cause of printing defects is that the cleaning liquid infiltrates into the fabric layer or the like of the support layer and swells the blanket in recent years when cleaning the blanket using a blanket solvent cleaning device (swelling) May cause peeling between support layers.) The cleaning liquid does not enter from the rubber surface of the surface rubber layer, but enters the inside of the support layer from the bottom of the blanket by capillary action from the exposed portion of the fabric on the side of the support layer. In addition, when cleaning with the blanket mounted on the blanket cylinder, the cleaning solution is not only exposed from the fabric layer on the side of the support layer, but also from the bottom of the blanket to the contact area with the blanket cylinder due to capillary action. It penetrates and penetrates into the blanket.

  As a device or an invention for solving the problem of the intrusion of the cleaning liquid, (1) a blanket (see, for example, Patent Document 2) in which a sealing layer is provided on the side surface of the support layer and the entire bottom layer of the blanket; A blanket (see, for example, Patent Document 3) in which a fluorine resin coating layer is provided on the surface of the fabric is disclosed.

However, in the blanket of (1), a sealing layer is provided on the entire side surface and back surface of the base fabric layer. However, since sealing is performed after the blanket is manufactured, not only is the sealing process difficult, but such sealing is not possible. There is a problem that the sealing effect is lost if cracks occur in the cracks, and the blanket base fabric of (2) is oil-repellent as a whole, so the adhesive strength with other support layers including sponge layers is sufficient. However, there is a problem in that printing failure or blanket damage is caused due to poor adhesion.
JP 47-32908 A Japanese Utility Model Publication No. 64-22462 Japanese Patent Laid-Open No. 3-158295

  The present invention has been made in view of such circumstances, and the side surface of the blanket while ensuring adhesion to a fabric or other support layer for preventing lateral movement of the surface rubber layer of the printing blanket. And providing a woven fabric for preventing the cleaning liquid from entering from the bottom surface, and using such a woven fabric to achieve the lateral movement of the surface rubber layer during printing or preventing the cleaning liquid from entering during cleaning. It is an object of the present invention to provide a printing blanket that achieves both preventions simultaneously.

  That is, the present inventor has conducted a series of studies in order to achieve the above object. A fabric using monofilaments with a predetermined fineness for the weft is effective in preventing the lateral movement of the surface rubber layer of the flanket at the time of printing pressure. When a base fabric having a difference in oil repellency between one side and the other side of the fabric is used for the bottom layer, etc., it is possible to effectively prevent the cleaning liquid from entering from the side and / or bottom of the blanket and The present inventors have found that the adhesiveness to the support layer is excellent and finally completed the present invention.

  That is, the first invention of the present invention is characterized in that the warp is a spun yarn or multifilament, the weft is a monofilament having a fineness of 50d to 300d, and the weft forms a linear state in the woven fabric. This is a printing blanket fabric.

  In this case, the spun yarn of the warp is exemplified by natural fibers such as cotton yarn, regenerated fibers such as rayon and lyocell, or spun yarns of synthetic fibers such as nylon, polyester and acrylic, and multifilaments such as rayon and lyocell. Examples include regenerated fibers or multifilaments of synthetic fibers such as nylon, polyester, and acrylic. As the weft monofilament, one having a fineness of 50d to 300d, preferably 70d to 200d, more preferably 100d to 150d may be used. However, if the length is less than 50d, the filament is insufficiently hard and it becomes difficult to maintain the linear state of the weft, and if it exceeds 300d, the balance with the fineness of the warp is lost and machine weaving becomes difficult. In the present invention, the straight state of the weft means that the monofilament as the weft is a straight line to a substantially straight line, and in a range that does not interfere with the effect of the present invention, a state in which a wave is formed by bending a little. Including.

  Of the present invention, the second invention uses warp yarns and oil-repellent weft yarns, and the amount of the weft yarns appearing on one side of the fabric is 60% to 80% in the area ratio represented by the fabric structure diagram. A printing blanket fabric characterized by the following.

  In the second invention, the type and material of the warp and weft are not particularly limited, but it is preferable to use spun yarn. In this case, examples of the spun yarn include natural fibers such as cotton yarn, as well as spun yarns of recycled fibers such as rayon and lyocell, or synthetic fibers such as nylon, polyester, and acrylic. The oil repellent process is not particularly limited as long as it is a process that imparts oil repellency to the yarn, and examples thereof include a process using a fluorine-based oil repellent. In the present invention, the area ratio represented by the woven structure chart is a numerical value representing the ratio of the number of wefts and warps in the structure chart in%.

A third invention of the present invention is a printing blanket having a surface printing layer and a support layer composed of at least one layer, wherein the fabric according to the first invention is used as a top layer of the support layer. Blanket for
A fourth invention is a printing blanket having a surface printing layer and a support layer composed of at least one layer, wherein the fabric according to the second invention is used for at least one layer of the support layer. And
In the fifth invention, the woven fabric according to the second invention is used for the bottom layer of the support layer, and the one side where the amount of the weft yarn appears as 60% to 80% in the area ratio is used as the bottom surface of the blanket. A printing blanket according to the fourth invention, characterized in that
A sixth invention is a printing blanket having a surface printing layer and a support layer composed of at least two layers, wherein the fabric according to the first invention is used as the support layer of the top layer, and the fabric according to the second invention is other than the top layer. A printing blanket characterized by being used for the support layer of
In the seventh invention, the woven fabric according to the second invention is used for the support layer of the bottom layer, and one side where the amount of the weft yarn appears as 60% to 80% in the area ratio is used as the bottom surface of the blanket. A blanket for printing according to the sixth aspect of the invention.

  In the printing blanket of the present invention, the surface printing layer is not particularly limited, but a conventional rubber printing layer can be exemplified. Further, the support layer composed of at least one layer is preferably a plurality of layers, and may include not only a woven fabric layer and a nonwoven fabric layer but also a sponge layer as a buffer layer.

  According to the woven fabric of the first invention, the weft is a monofilament having a predetermined fineness, and is woven in a hard and straight state. Like a woven fabric, the weft does not shrink in the length direction along with the extension in the warp direction and maintains a linear state. Therefore, the weft direction is also affected by the tension during high-speed printing operation and the mounting tightening pressure when the blanket is installed. Hardly grows. Therefore, the fabric of the first invention used as a blanket support for printing can sufficiently prevent the lateral movement of the rotating blanket surface printing layer in the rotating direction. Even if there is an increase in printing pressure associated with BB type printing, it is possible to ensure clear printing without causing printing failure or paper separation failure due to lateral movement of the surface printing layer. In addition, the fabric of the first invention used as a printing blanket support is generated when two blankets are attached to one cylinder in newspaper printing or the like because the wefts maintain a linear state and do not shrink. Some so-called hourglass phenomenon can also be prevented, and furthermore, since the weft is a monofilament, the penetration of the cleaning liquid into the blanket due to the capillary phenomenon through the weft does not occur.

  According to the woven fabric of the second invention, oil-repellent processed weft is used, and the amount of this weft that appears on one side of the woven fabric is 60% to 80% in the area ratio represented by the woven fabric structure chart. When the woven fabric of the invention 2 is used as a support layer for a printing blanket, (1) at the time of washing the printing blanket, the end portion appears on the side of the printing blanket, and the washing liquid has been infiltrated into the blanket by capillary action. Since the weft is oil-repellent processed, the penetration of the cleaning liquid from the side of the blanket can be sufficiently prevented, and (2) the amount of oil-repellent processed weft appearing on both sides of the fabric is provided with a predetermined difference. On the surface where a large amount of weft appears, it is possible to prevent the intrusion of the cleaning liquid, and on the surface where the amount of weft is small, adhesion inhibition due to oil repellent processing is small, and sufficient adhesion to other layers can be secured. That. In particular, in bonding with the sponge layer, it is possible to perform processing at low pressure without applying high pressure in the bonding processing step, so that collapse of bubbles (balloons) in the sponge layer caused by high pressure processing can be prevented, or Does not hinder the generation of bubbles. That is, this woven fabric has a composite function capable of ensuring adhesion on the other surface while preventing the cleaning liquid from entering on one surface in the blanket.

  According to the third invention, in the printing blanket having the surface printing layer and the support layer composed of at least one layer, the woven fabric according to the first invention is used for the top layer of the support layer. The fabric can directly prevent the lateral movement of the surface printing layer, and this blanket can more reliably prevent printing defects due to the lateral movement of the conventional printing layer. Further, since the weft is a monofilament, it is possible to prevent the cleaning liquid from entering from the side of the blanket in the top layer of the support layer.

  According to the fourth invention, in the printing blanket having the surface printing layer and the support layer composed of at least one layer, the fabric according to the second invention is used for at least one layer of the support layer. In this case, the layer using the woven fabric can prevent the cleaning liquid from entering from the side of the blanket. In this case, the surface where the appearance of the weft is small does not use a rubber adhesive with specially improved adhesiveness, and can be bonded to, for example, a sponge layer even in a low pressure bonding process. On the other hand, the surface where wefts frequently appear can be sufficiently bonded by low-pressure processing using an adhesive such as ordinary rubber except for the sponge layer. It is possible to prevent the cleaning liquid from entering the blanket from the surface. Therefore, for example, when the woven fabric according to the second invention is used for all of the support layers, the adhesive between the woven fabrics requires an adhesive such as rubber, but the infiltration of the cleaning liquid from the entire side surface and the bottom surface of the blanket. Can be prevented. Also, for example, when a sponge layer is provided on the support layer and all the other support layers are made into a woven fabric according to the second aspect of the invention, the woven fabric is formed by directing the woven fabric surface with less appearance of the weft to the sponge layer. In the same manner as described above, it is possible to prevent the cleaning liquid from entering from the entire side surface and the bottom surface of the blanket, while eliminating the need for an adhesive such as rubber with specially improved adhesion between the sponge layers.

  According to a fifth aspect of the present invention, in the printing blanket, the surface in which the woven fabric according to the second aspect is used for the bottom layer of the support layer and the amount of the weft appears as 60% to 80% in the area ratio (that is, the above-mentioned Since the surface on which the weft appears frequently becomes the bottom surface of the blanket, it is possible to prevent the cleaning liquid from entering from the bottom surface of the blanket and to prevent the cleaning liquid from entering from the side surface of the blanket in the bottom layer. Therefore, the woven fabric of the present invention is used in the bottom layer, and (1) a woven fabric (for example, the woven fabric or plain woven fabric of the present invention) in which at least wefts are oil-repellent processed, or (2) the entire layer is oil-repellent processed. If the woven fabric or the nonwoven fabric is used and the support layers are bonded with an adhesive, it is possible to prevent the cleaning liquid from entering from all the side surfaces and the bottom surface of the blanket.

  According to the sixth invention, in a printing blanket having a surface print layer and a support layer composed of at least two layers, the fabric described in the first invention is used as the support layer of the top layer, and the fabric described in the second is used as the top. The blanket does not extend in the weft direction due to the printing pressure during printing because of the use of the support layer other than the layer as a result of the fabric according to the first invention. Even if there is an increase in printing pressure due to the B-B printing, printing failure due to lateral movement of the blanket surface printed layer does not occur, and these are further reduced by the fabric according to the first invention and the fabric according to the second invention. It is possible to prevent the cleaning liquid from entering from the side of the layer using the fabric.

  In particular, in the printing blanket of the sixth invention, as in the seventh invention, the woven fabric described in the second invention is placed on the support layer of the bottom layer, and the surface on which the wefts frequently appear is the bottom surface of the blanket. If used, the fabric of the second invention can prevent the cleaning liquid from entering from the bottom of the blanket. Therefore, according to the seventh invention, the woven fabric according to the first invention does not cause printing failure due to the lateral movement of the blanket surface printed layer, and the woven fabric according to the first invention and the woven fabric according to the second invention. It is possible to prevent the cleaning liquid from entering from the side surface of the layer using the fabric and the penetration of the cleaning liquid from the bottom surface.

(1) is a schematic diagram of a longitudinal section of a woven fabric in which the weft yarn according to the present invention is a monofilament and is in a linear state, and (2) is a schematic diagram of a transverse section of the woven fabric. These are the schematic block diagrams which show an example of the lamination | stacking state of the surface rubber layer of the printing blanket which concerns on this invention, and each layer of a support body. These are the schematic diagrams which show an example of the state of the monofilament which should be employ | adopted in the manufacturing process of the textile fabric in which the weft which concerns on this invention is a monofilament and a linear state. These are examples of the structure | tissue chart which showed the surface side with much appearance of a weft in the twill fabric using the weft after oil-repellent finish which concerns on this invention. (1) is a graph showing a tensile test result (stress-strain curve) of a woven fabric in which the wefts according to the present invention are monofilaments compared with a conventional four-layer laminate, and (2) is (1). ) Is a partially enlarged view of the graph with a test force (N) of 200 and a stroke (strain) of up to 10%. These are the schematic diagrams of the printing process of the printing unit containing a BB type offset printing machine blanket cylinder.

  Next, the present invention will be described in more detail with reference to examples. However, these are only specific examples for implementing the present invention and results (effects) thereof, and the present invention is not limited to these examples. There are no restrictions.

Example 1
A plain woven fabric having a weft in a straight state was prepared as follows using a polyester monofilament (manufactured by Toray Monofilament Co., Ltd.) having a fineness of 150 d for the weft and a 60th cotton double yarn for the warp. That is, for example, using a loom (Sultec Japan Projectile), as shown in FIG. 3, a weft 11 (not shown) is driven into the warp so that the weft 11 is slightly loosened. When the weft yarn is struck and woven into the pre-folding 13 in this case, the monofilament is hard, so that the weft as shown in FIG. 1 is woven in a straight line. Since this woven fabric is used as a blanket support, even if it is stretched in the radial direction, the straight state of the weft is maintained.

(Example 2)
Using a polyester monofilament (made by Uniplus Shiga Co., Ltd.) having a fineness of 100d for the weft yarn and a 60th cotton double yarn for the warp yarn, a plain fabric (see FIG. 1) in which the weft yarn is in a straight state was prepared in the same manner as in Example 1. . This woven fabric is also used as a blanket support, so that the linear state of the weft is maintained even if it is stretched in the radial direction.

(Example 3)
First, the 30th cotton single yarn was oil-repellent processed using a fluorine-based oil repellent finishing agent (NK Guard manufactured by Nikka Chemical Co., Ltd.). Next, a twill woven fabric shown in the organization chart of FIG. 4 was manufactured using this oil-repellent cotton single yarn as a weft and a 30th cotton double yarn as a warp. In this case, the amount of the weft appearing on one side of the woven fabric is a numerical value representing the ratio of the number of wefts (white eyelets) and warps (black eyelets) in the woven fabric structure diagram in terms of%, (81/108) × 100 = 75%.

Example 4
In the first layer, a plain woven fabric having a warp of 60th cotton double yarn and a weft of 30th cotton single yarn having a thickness of 0.25 to 0.26 mm,
In the second layer, a warp is a 30th cotton twine, a weft is a 30th cotton single yarn, and a plain fabric having a thickness of 0.30 to 0.31 mm,
In the third layer, a warp is a 30th cotton double yarn, a weft is a 30th cotton single yarn, and a plain woven fabric having a thickness of 0.30 to 0.31 mm,
In the fourth layer, a warp is a 20th cotton double yarn, a weft is a 20th cotton single yarn, and a plain woven fabric having a thickness of 0.38 to 0.39 mm is used. Were bonded with a rubber adhesive and stretched in the longitudinal direction to prepare a blanket support 3 (residual elongation in the warp direction was about 4% or less).

  Next, the fabric prepared in Example 1 was used as a blanket support 1, and the fabric prepared in Example 2 was used as a blanket support 2. A tensile tester (Shimadzu Corporation) was applied to the support 1, support 2, and support 3. A tensile test was performed in accordance with JIS K6301. The result is shown in FIG.

  In spite of the fact that the support 1 and the support 2 are one-layer fabrics, in the initial modulus (up to about 100 N load), the modulus in the weft direction is that of the support 3 composed of four-layer fabrics. The modulus was several times larger than the modulus in the weft direction, and was close to the modulus in the warp direction. Therefore, considering the actual printing pressure (up to about 2N), the weft direction elongation of the woven fabric of the present invention approximates the warp direction elongation of one conventional four-layer support layer during printing. Only a certain degree of elongation will be exhibited, and the reinforcing effect substantially the same as the warp direction of the conventional four-layer support will be exhibited.

(Example 5)
For the surface rubber layer 3, the fabric 5 of Example 1 or Example 2 is used as the top layer of the support layer 4, and the sponge layer 6, the third layer, the fourth layer, and the bottom layer are formed on the second layer of the support layer 4. FIG. 2 shows a schematic schematic configuration diagram of a printing blanket prepared using the fabrics 7, 8, and 9 of Example 2 (the bottom layer has a surface with a lot of oil-repellent wefts as the bottom side of the blanket). Show. In this case, the fabric layer 7 of the third layer is in contact with the sponge layer side of the third layer fabric 7 and the surface of the fabric 9 where the weft yarn appears is the bottom side of the blanket. Further, in this case, the interface between the sponge layer 6 and the fabric 7 was not used with a rubber adhesive with specially improved adhesion, and a normal rubber adhesive was used in the same manner as other interfaces.

  In this blanket, due to the reinforcing effect of the top layer 5 of the support layer 4, there is no lateral movement of the surface rubber layer 3 during printing, and only vertical movement occurs, so printing defects occur. In addition, when the blanket is washed, the monofilament wefts of the top layer 5 and the end portions of the oil repellent wefts of the third layer to the bottom layer appear on the side surface of the blanket. Furthermore, since the bottom surface of the blanket is a surface (75% in area ratio) where the weft of the fabric of Example 3 appears frequently, the penetration of the cleaning liquid from the bottom surface of the blanket can be sufficiently prevented.

  This invention is suitably used as a support for a printing blanket surface printing layer.

DESCRIPTION OF SYMBOLS 1 Weft 2 Warp 3 Surface printing layer 4 Support layer 5 Fabric according to the present invention in which the weft is a monofilament 6 Sponge layer 7 Fabric according to the present invention in which the weft is an oil repellent yarn 8 Same as above 9 Same as above 11 Weft in a relaxed state 12 Weave Previous 13 Support 1 Weft-direction stress-strain curve 14 Support 2 Weft-direction stress-strain curve 15 Support 3 Warp-direction stress-strain curve 16 Support 3 Weft-direction stress-strain curve

Claims (3)

Blanket fabric for printing, characterized in that warp and weft treated with oil repellency are used, and the amount of the weft that appears on one side of the fabric is 60% to 80% in the area ratio shown in the fabric structure diagram. . A printing blanket having a surface printing layer and a support layer comprising at least one layer, wherein the fabric according to claim 1 is used for at least one layer of the support layer. The woven fabric according to claim 1 is used for a bottom layer of a support layer, and one side where the amount of the weft is 60% to 80% in area ratio is used as a bottom surface of the blanket. The printing blanket according to claim 2.