JP5586434B2 - Dust removal blanket for printing - Google Patents

Description

  The present invention relates to a dust removal blanket for printing.

  In offset printing, ink or paper dust accumulates on the printing blanket, particularly at the periphery of the image area, and rises, and this causes a so-called blanket piling phenomenon that affects printing quality. When this phenomenon occurs, the transfer of ink from the printing blanket to the printing paper is inhibited in the vicinity thereof, resulting in scumming or a decrease in density, thereby deteriorating the printing quality. For this reason, it is necessary to take measures such as temporarily stopping the printing press and carrying out blanket cleaning to remove deposits.

  In a multi-color rotary printing press, the operation rate of the printing press decreases and material loss (damaged paper) occurs due to the stoppage and cleaning time. In order to solve these problems, techniques for preventing blanket piling by improving printing materials and members have been proposed in Patent Documents 1 to 3, for example, but sufficient effects have not been obtained.

  Patent Document 4 discloses a dust collection device. In the dust collecting device of Patent Document 4, the air blowing nozzle and the suction duct are arranged with a slitter knife or the like interposed therebetween, and the air flowing in the same direction as the traveling direction of the sheet material is blown out from the air blowing nozzle. The following problems may occur. Paper dust generated when the paper is cut with a slitter knife is rolled up backward in the paper traveling direction. Then, the rolled up paper dust is blown forward by an air blowing nozzle. This paper dust is sucked by the suction duct, but some paper dust is not attracted and trapped by the air flow. In particular, the paper dust accompanying the travel of the sheet material is not easily attracted and captured by the air flow and is not easily sucked by the suction duct. For this reason, there exists a possibility that the paper dust which passes a suction duct may generate | occur | produce. Since the paper dust that has passed through the suction duct will not be removed thereafter, it will drop and adhere to the surface of the sheet material, and will be used in processes such as printing. In addition, when the suction duct is brought close to the sheet material so that the paper powder accompanying the travel of the sheet material can be reliably sucked, the sheet material contacts the suction duct because the sheet material is cut behind the slitter knife. There is a risk of hitting or sucking.

  In addition, in the paper dust removing device disclosed in Patent Document 5, when the paper dust released from the paper surface by high-speed air is not sucked by the suction device, it is scattered in the atmosphere, thereby deteriorating the working atmosphere. There is a fear. In addition, since the paper dust removing device is arranged at a roller portion that changes the traveling direction of the paper, if the portion is farther from the location where the paper dust is generated, before the paper dust removing device is used. There is a possibility that paper dust has already been scattered in the atmosphere.

  Patent Document 6 discloses an adhesive roller that removes paper dust that comes into contact with a printing paper and adheres to the printing paper, and an adhesive roller regeneration adhesive tape that comes into contact with the adhesion roller and removes paper dust attached to the adhesion roller. A paper dust removing device for a printing press comprising: According to the apparatus of Patent Document 6, a dedicated facility for attaching the adhesive roller and the adhesive tape for reproducing the adhesive roller is required. Therefore, there exists a problem that the said adhesive roller cannot be employ | adopted as a printing machine without remodeling at all.

  On the other hand, in Patent Document 7, the adhesive sheet is detachably attached to the printing unit as a covering material, and the adhesive sheet comes into contact with the paper immediately before printing to adhere the paper powder, thereby removing the adhesive of the paper paper powder. A paper dust removing device to perform is disclosed. Since the pressure-sensitive adhesive sheet described in Patent Document 7 is made of a fluid-based pressure-sensitive adhesive such as rubber, plastic deformation tends to occur when pressure is applied to the pressure-sensitive adhesive sheet by contacting the paper with the pressure-sensitive adhesive sheet. Therefore, the surface of the pressure-sensitive adhesive sheet is deformed with the adhesion of paper dust, and the paper dust is caught inside the pressure-sensitive adhesive. Once the paper dust adheres to the pressure-sensitive adhesive sheet, There is a problem that the paper dust inside the agent cannot be removed and therefore cannot be reused.

JP 09-295469 A Japanese Patent Laid-Open No. 08-1113748 Japanese Patent Laid-Open No. 11-140791 Japanese Patent Laid-Open No. 10-156696 JP 2002-200591 A JP-A-1-136748 Japanese Patent Laid-Open No. 1-154758

  An object of this invention is to provide the dust removal blanket for printing excellent in the dust removal effect.

According to an embodiment of the present invention, a dust removal blanket for printing that removes dust attached to a print medium by contacting the print medium before printing,
A surface rubber layer having an adhesive strength of 1 to 500 mN / cm with respect to the printing medium;
And a support layer for supporting the surface rubber layer , wherein the support layer includes a base fabric layer and a compression layer .

  ADVANTAGE OF THE INVENTION According to this invention, the dust removal blanket for printing excellent in the dust removal effect is provided.

Sectional drawing which shows typically the dust removal blanket for printing of an Example. 1 is a diagram illustrating a schematic configuration of a multicolor printer used in an embodiment. FIG.

  Hereinafter, embodiments of the present invention will be described in detail.

  A printing dust removal blanket (hereinafter also simply referred to as a dust removal blanket) according to an embodiment includes a surface rubber layer having an adhesive strength of 1 to 500 mN / cm with respect to a printing medium, and a support for supporting the surface rubber layer. And a layer. Note that if the printing blanket is sticky, paper dust and foreign matter (hereinafter referred to as paper dust) accumulate, and blanket piling occurs, which leads to poor printing. In addition, the print medium sticks, causing printing misalignment and jamming (paper jam).

  The dust removal blanket for printing captures the paper dust attached to the printing medium on the blanket by bringing the printing medium before printing into contact with the surface rubber layer, and removes the paper dust etc. from the printing medium repeatedly. It is for use. The blanket is preferably used by being incorporated in a printing press, but can be used by being incorporated in an apparatus different from the printing press. Applicable printing machines include, for example, offset printing machines. Since the shape of the dust removal blanket can be the same as or substantially the same as that of the printing blanket, a dedicated facility for attaching the dust removal blanket to the printing press is unnecessary, and it can be attached to the printing press as it is. Also, when removing dust from media printed on a multi-color printer, if there is an extra blanket cylinder that is not used before ink transfer in this printer, attach a dust removal blanket to this blanket cylinder. This makes it possible to incorporate a dust removal blanket during the printing process (in-line).

  First, the surface rubber layer will be described.

  The surface rubber layer has an adhesive strength of 1 to 500 mN / cm with respect to the printing medium. There are various types of media to be printed, such as paper, coated paper, film, and metal. If the material changes, even the surface rubber layer with the same composition can change the adhesive strength. It has been found that a surface rubber layer having an adhesive strength of 1 to 500 mN / cm with respect to the medium can provide an excellent dust removal effect regardless of the type of printing medium.

  That is, when the adhesive strength is less than 1 mN / cm, the adhesive strength of the surface rubber layer is too low to capture paper dust or the like. On the other hand, when the adhesive strength exceeds 500 mN / cm, the adhesive strength of the surface rubber layer is too strong, and the print medium is hardly peeled off from the surface rubber layer, and defects such as jamming and tearing are likely to occur. Although the preferable range of the adhesive strength may vary depending on the type of printing medium, in order to obtain a defect prevention effect such as jamming and tearing on various printing media and a dust removal effect, the range is 1 mN / cm or more and 200 mN / cm. In order to suppress the change in the adhesive strength before and after dust removal, and more preferably in the range of 50 mN / cm or more and less than 200 mN / cm.

  The print medium may be a printable medium. The printing medium is not limited to the type that is actually printed by the printing machine, and a dust removal effect can be expected as long as the printing medium can be printed by the printing machine. Examples of the printing medium include inner and outer materials such as renewal paper, newspaper, cardboard, coated paper, synthetic paper, label, card, banknote, wallpaper, film, cloth, metal, glass, rubber, and the like. The printing medium is not limited to these. The metal may be either a flat plate such as a metal plate or a solid shape having a curved surface such as a can.

The adhesive strength is measured under the following conditions that are partially in accordance with JISK6854. First, the dust removal blanket is cut into a size of 20 × 200 mm to obtain a measurement sample A (a dust removal blanket sample). The print medium before dust removal by the dust removal blanket is cut into a size of 25 × 220 mm to obtain measurement sample B (sample of print medium). The surface rubber layer of the sample A for measurement is coated with the sample B for measurement in a temperature 20 ± 5 ° C. and humidity 65 ± 20% RH environment so that air bubbles do not enter these interfaces, and is applied at 15 N / cm ² for 30 seconds. Press. After releasing the pressure, the measurement sample A and the measurement sample B are peeled 150 mm at a speed of 1000 mm / min in the direction of 180 degrees in 10 ± 5 minutes, and the average of the adhesive strength at that time is measured. The obtained value is defined as the adhesive strength for the printing medium.

  The rubber contained in the surface rubber layer is not particularly limited. For example, natural rubber, styrene butadiene rubber (SBR), nitrile rubber (NBR), chloroprene, butyl rubber (IIR), ethylene propylene rubber (EPDM), Examples thereof include chlorosulfonated polyethylene (CSM), silicone rubber, and fluororubber. The type of rubber used can be one type or two or more types. Further, it is desirable to select a rubber type according to the blanket cleaning agent.

  A vulcanizing agent (for example, sulfur), a vulcanization accelerator, or both are added to the surface rubber layer. Examples of vulcanization accelerators include D.I. And M (dibenzothiazole, disulfide) and M (2-mercaptobenzothiazole). Further, the surface rubber layer may contain additives such as an anti-aging agent, a reinforcing agent, a filler, a plasticizer, titanium oxide, and a clay mainly containing hydrous aluminum silicate. The clay mainly composed of titanium oxide and hydrous aluminum silicate can improve the strength and durability of the surface rubber layer. Moreover, since the adhesive force of a surface rubber layer will become low when the clay of a titanium oxide and hydrous aluminum silicate main component is added, adhesive force can be adjusted.

  The surface rubber layer is produced, for example, by vulcanizing a sheet of a composition containing rubber. The adhesive strength of the surface rubber layer can be expressed, for example, by selecting the type of rubber and plasticizer. As a selection of rubber and plasticizer that develops adhesive force, a combination of butyl rubber and a naphthenic oil of plasticizer (for example, trade name, Diana Process Oil NP24 manufactured by Idemitsu Kosan Co., Ltd.) can be given. By vulcanizing a sheet of a composition containing butyl rubber and naphthenic oil, an adhesive force can be imparted to the surface rubber layer. In addition, since elasticity is imparted to the surface rubber layer by vulcanization, plastic deformation such as thickness reduction associated with the use of a dust removal blanket can be suppressed. Further, unlike the pressure-sensitive adhesive sheet in which paper dust or the like is wound inside the pressure-sensitive adhesive, the surface rubber layer does not wind paper dust or the like in the inside thereof, so that the adhesive strength can be recovered after washing.

  The adhesive strength of the surface rubber layer can be controlled to a desired value by changing the contact area with the printing medium, for example, by changing the surface roughness of the surface rubber layer. For example, if the surface rubber layer is vulcanized in a state where the surface of the surface rubber layer is covered with a polyethylene terephthalate (PET) film having a mirror surface, the surface rubber layer after peeling the PET film is mirror-finished and the contact area with the printing medium increases. Therefore, the adhesive strength of the surface rubber layer can be increased. On the other hand, when the surface rubber layer is coated with a rough surface film (mat film) produced by roughening the surface of the PET film and vulcanized, the surface rubber layer becomes rough and the surface rubber layer The adhesive strength can be lowered. In addition, after the vulcanization of the dust removal blanket, the surface rubber layer can be roughened by polishing the surface rubber layer, so that the adhesive strength of the surface rubber layer can be lowered. . The sheet used for coating is not limited to a resin film such as a PET film, and for example, a cloth may be used. It is also possible to change the adhesive strength of the surface rubber layer by blending the rubber composition without changing the surface roughness.

  The support layer is disposed on the back side of the front rubber layer. Since the surface rubber layer has adhesiveness, the wearability of the dust removal blanket can be improved by disposing the support layer on the back side of the surface rubber layer. Further, deformation (elongation) of the surface rubber layer when the dust removal blanket is mounted on the blanket cylinder can be suppressed. The support layer includes at least one base fabric or film. The number of base fabrics or films constituting the support layer is not particularly limited and may be plural. Both the base fabric and the film can be included in the support layer. Base fabric is made of, for example, cotton, wool, hemp, silk, rayon, cupra, acetate, nylon, vinylon, polyester, polyvinyl chloride (PVC), acrylic, acrylate, carbon fiber, aramid, polyimide, metal fiber or glass fiber Can be formed. The type of material forming the base fabric can be one type or two or more types. Examples of the film include a resin film such as a PET film, a metal film, and the like.

  An example of a dust removal blanket for printing is shown in FIG. FIG. 1 is a cross-sectional view schematically showing a printing dust removal blanket according to an embodiment. As shown in FIG. 1, the dust removing blanket 1 for printing includes a support layer 2 and a surface rubber layer 3 laminated on the support layer 2. The support layer 2 is laminated with a base fabric layer 4 made of, for example, cotton cloth, a compressed layer 6 laminated on the base fabric layer 4 via an NBR adhesive layer 5, and a compressed layer 6 laminated with an NBR adhesive layer 7. A base fabric layer 8 (made of cotton, for example), a solid layer 10 laminated on the base fabric layer 8 via an NBR adhesive layer 9, and a base fabric layer 12 laminated on the solid layer 10 via an NBR adhesive layer 11 (For example, made of cotton cloth). Thus, the layer (for example, a base fabric layer, a compression layer, etc.) which consists of at least one layer arrange | positioned at the back surface side of the surface rubber layer 3 is named the support body layer 2 generically.

  The configuration of the support layer 2 is not limited to that illustrated in FIG. For example, a compression layer 6 may be disposed between the base fabric layer 4 and the surface rubber layer 3 and integrated with these layers may be used for the support layer. Further, the compression layer may be provided between the base fabric layer disposed on the back surface of the front rubber layer and at least one base fabric layer disposed on the back surface side of the base fabric layer. Adhesion between the layers constituting the blanket can be performed by, for example, an adhesive layer.

  The adhesive layer and the compression layer can be obtained, for example, by vulcanizing a rubber compound sheet. In addition, it is possible to use a nonwoven fabric as a compression layer instead of the vulcanized rubber compound sheet. Examples of the rubber contained in the rubber compound include acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), fluorine rubber (FKM), polyurethane rubber (UR), ethylene propylene rubber (EPDM), butyl rubber (IIR), and the like. Nonpolar polymers can be used. In addition to the rubber material, the rubber compound preferably contains an additive for obtaining a rubber elastic body. Examples of the additive include a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, a reinforcing agent, a filler, and a plasticizer.

  The compression layer can be a porous structure such as a sponge or a solid structure. As a method for forming the porous structure, for example, addition of microcapsules, a method using impregnated paper, a salt elution method, a foaming agent method, and the like can be employed.

  Paper dust or the like captured by the printing dust removal blanket adheres to the surface rubber layer, but the printing dust removal blanket can be used repeatedly by washing the surface rubber layer. Cleaning may be performed by wiping with a solvent, blowing air, or removing with an adhesive tape or an adhesive roll. The reason why the surface can be repeatedly used after washing is that a sticky rubber surface appears by removing paper dust and the like covering the surface. Since the surface rubber layer is an elastic body, it can be restored to its original shape after washing. In the case of solvent washing, it is necessary to select a solvent that does not dissolve the rubber. When the surface rubber layer is immersed in a solvent, a solvent film is formed between the rubber and the paper dust, and the adhesive strength is lost while wet, so that the paper dust can be easily removed. When dried, the adhesive strength is restored to the initial level. The cleaning of the surface rubber layer may be performed during the dust removal by the dust removal blanket or during the suspension of the dust removal operation. When performing during dust removal, the method of removing the paper dust etc. which adhered on the surface rubber layer with an adhesive tape is mentioned, for example.

  According to the dust removal blanket for printing according to the embodiment described above, since the surface rubber layer having an adhesive strength of 1 to 500 mN / cm with respect to the printing medium is provided, the printing medium is passed through the blanket. Paper dust and the like attached to the printing medium can be removed. At that time, since the blanket is in direct contact with the printing medium and collects paper dust and the like by adhesive force, the scattering of paper dust and the like into the atmosphere during dust removal can be greatly reduced. Therefore, it is possible to increase the removal rate of paper dust and the like adhering to the printing medium, and it is possible to prevent the paper dust and the like from reattaching to the printing medium. (Blanket piling) can be reduced and hicky defects can be reduced.

  In addition, since the printing medium passes smoothly over the blanket, defects such as jamming and tearing due to the printing medium sticking to the blanket can be reduced, and paper feedability is achieved.

  Furthermore, by making the dust removal blanket the same shape as the printing blanket, it can be used immediately just by mounting it on the blanket cylinder of various printing machines such as offset printing press, rotary printing press, sheet-fed printing press, etc. Can be made unnecessary. Further, a dust removing blanket for printing can be attached to one or both of a pair of dust removing (printing) blanket cylinders in a printing unit of various printing machines, and paper dust and the like can be removed from one or both sides of a printing medium. . Furthermore, since the surface rubber layer has elasticity, it is difficult for plastic deformation to occur due to the pressure applied during the dust removal treatment, and deformation of the surface shape can be reduced. As a result, paper dust or the like is not caught inside the surface rubber layer, so that paper dust or the like can be easily removed from the surface rubber layer by washing, and the dust removal blanket can be repeatedly used by washing.

  Next, examples of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following examples.

Example 1
100 parts by weight of butyl rubber (trade name manufactured by Policer; butyl 402), 20 parts by weight of titanium oxide, 40 parts by weight of clay containing hydrous aluminum silicate, naphthenic oil as a plasticizer (trade name of Idemitsu Kosan Co., Ltd .; Diana Process) Oil NP24) 30 parts by weight and 2 parts by weight of sulfur as a vulcanizing agent were kneaded to obtain a rubber compound.

  As a support layer, in order from the layer disposed on the back surface of the front rubber layer, a cotton cloth (first base cloth layer) 4, an NBR adhesive layer 5, a compression layer (NBR porous layer containing a microballoon) 6, an NBR adhesion A laminate composed of layer 7, cotton cloth (second base fabric layer) 8, NBR adhesive layer 9, NBR solid layer 10, NBR adhesive layer 11, and cotton cloth (third base fabric layer) 12 was prepared. This laminate was vulcanized at 150 ° C. for 120 minutes to form a support layer having a total thickness of 1.5 mm.

  A surface rubber layer was formed on the support layer by topping the rubber compound with a thickness of 0.5 mm on the support layer. The surface rubber layer was coated with a rough film (trade name, manufactured by Teijin DuPont Films; Teijin Matte Film F2700-PS, thickness 250 μm), vulcanized at 160 ° C. for 60 minutes, and the coated film was peeled off. A dust removal blanket was obtained. The obtained dust removal blanket was polished with a silicon carbide # 80 polishing cloth at a dust removal blanket feed speed of 2 m / min and a polishing cloth speed of 1000 m / min, and the adhesive strength between the sheet and the surface rubber layer was 5 mN / cm. A dust removal blanket having the structure shown in FIG. In addition, the measurement of adhesive strength was performed by the method mentioned above.

(Example 2)
A dust removal blanket was obtained under the same conditions as in Example 1 except that a woven fabric (trade name, manufactured by Iwao Co., Ltd .; polyester woven fabric # 5075 production machine) was used in place of the rough surface film and polishing was not performed. . The smoothness of the woven fabric was lower than that of the rough film, so that the polishing process was not performed, and the adhesive strength between the paper and the surface rubber layer was 51 mN / cm.

(Example 3)
A dust removal blanket was obtained in the same manner as in Example 1 except that the polishing conditions were a silicon carbide # 2000 polishing cloth, a dust removal blanket feed speed of 2 m / min, and a polishing cloth speed of 1000 m / min. Since the smoothness of the surface rubber layer was increased by reducing the roughness of the polishing cloth, the adhesive strength between the sheet and the surface rubber layer was 185 mN / cm.

Example 4
A dust removal blanket was obtained in the same manner as in Example 1 except that the polishing process was not performed. Since the polishing process was not performed, the smoothness of the surface rubber layer was high, and the adhesive strength between the additional paper and the surface rubber layer was 475 mN / cm.

(Comparative Example 1)
A dust removal blanket was obtained under the same conditions as in Example 1, except that a PET film having a mirror surface thickness of 125 μm (trade name; manufactured by Unitika; polyester film EMBLET SA) was used instead of the rough surface film. The obtained dust removal blanket is polished with a silicon carbide # 40 polishing cloth at a dust removal blanket feed speed of 2 m / min and a polishing cloth speed of 1000 m / min to obtain a dust removal blanket having an adhesive strength of 0.2 mN / cm. It was.

(Comparative Example 2)
A dust removal blanket was obtained in the same manner as in Comparative Example 1 except that the polishing process was not performed. The adhesive strength between the re-paper and the surface rubber layer was 800 mN / cm.

(Comparative Example 3)
The acrylic adhesive was coated on a non-woven fabric having a thickness of 0.1 mm to a thickness of 0.05 mm to obtain an adhesive sheet having an adhesive strength of 3000 mN / cm between the additional paper and the surface adhesive layer.

(Comparative Example 4)
A rubber adhesive was coated on a 0.1 mm thick non-woven fabric to a thickness of 0.1 mm to obtain an adhesive sheet having an adhesive strength of 6000 mN / cm between the additional paper and the surface adhesive layer.

(Example 5)
Using the dust removal blanket obtained in Example 1, the medium to be printed was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured, and it was 7 mN / cm.

(Example 6)
Using the dust removal blanket obtained in Example 2, the medium to be printed was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured. As a result, it was 60 mN / cm.

(Example 7)
Using the dust removal blanket obtained in Example 3, the printing medium was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured, and it was 195 mN / cm.

(Example 8)
Using the dust removal blanket obtained in Example 4, the printing medium was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured, and it was 490 mN / cm.

(Comparative Example 5)
Using the dust removal blanket obtained in Comparative Example 1, the medium to be printed was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured and found to be 0.5 mN / cm.

(Comparative Example 6)
Using the dust removal blanket obtained in Comparative Example 2, the medium to be printed was changed to a PET film, and the adhesive strength between the PET film and the surface rubber layer was measured and found to be 900 mN / cm.

(Comparative Example 7)
Using the pressure-sensitive adhesive sheet obtained in Comparative Example 3, the printing medium was changed to a PET film, and the adhesive strength between the PET film and the surface pressure-sensitive adhesive layer was measured to be 3300 mN / cm.

(Comparative Example 8)
Using the pressure-sensitive adhesive sheet obtained in Comparative Example 4, the printing medium was changed to a PET film, and the adhesive strength between the PET film and the surface pressure-sensitive adhesive layer was measured. As a result, it was 6500 mN / cm.

The dust removal blanket produced above was attached to the multicolor printer shown in FIG. FIG. 2 shows a schematic configuration of the multicolor printer used in the embodiment. The multicolor printer 20 includes a paper feeding unit 21, a dust removing unit 22, a printing unit 23, and a paper discharge unit 24. The paper feed unit 21 conveys the renewal paper and the PET film as the printing medium X, and supplies them to the dust removal unit 22. The dust removal unit 22 has a pair of dust removal blanket cylinders 25a and 25b. Each of the dust removal blanket cylinders 25a and 25b is obtained by mounting a dust removal blanket on a blanket cylinder that is always provided in a multicolor printer. Printing unit 23 for performing 4-color printing comprises four printing units 26 ₁ to 26 _4. Each of the printing units 26 _{1 to} 26 ₄ has a pair of printing blanket cylinders 27a and 27b, and plate cylinders 28a and 28b for transferring the plates to the printing blanket cylinders 27a and 27b, respectively. Each of the printing blanket cylinders 27a and 27b is obtained by mounting a printing blanket on the blanket cylinder. The paper discharge unit 24 is arranged at the subsequent stage of the printing unit 23.

The printing medium X transported from the paper feeding unit 21 to the dust removing unit 22 passes between the dust removing blanket cylinders 25a and 25b, so that paper dust and the like are simultaneously removed from the front and back sides. After dust removal process, the printing medium X is a printing unit 26 ₁ to 26 ₄ of the printing blanket cylinder 27a of the printing unit 23, by passing between 27b, front and back at the same time successively four-color printing is performed. The printed medium X is supplied to the paper discharge unit 24.

In the multi-color printing press configured as described above, the adhesive strength when feeding 10000 sheets of printing medium X between the dust removal blanket cylinders 25a and 25b with a pressure of 0.4 N / cm ² , paper feeding suitability, paper dust / foreign matter removal The effect was confirmed. Table 1 shows the results when using renewed paper (Examples 1 to 4 and Comparative Examples 1 to 4), and Table 2 shows results when using PET films (Examples 5 to 8 and Comparative Examples 5 to 8). Shown in

  After measuring the adhesive strength after feeding 10,000 sheets, for Examples 1 to 8 and Comparative Examples 1, 2, 5, and 6, the surface of the surface rubber layer was wiped and washed using methyl ethyl ketone (MEK) solvent, For Comparative Examples 3, 4, 7, and 8, the surface of the adhesive sheet was washed using an adhesive roller. The reason why the cleaning of Comparative Examples 3, 4, 7, and 8 is performed using the adhesive roller is that when the cleaning is performed with the MEK solvent, the adhesive is separated. After washing, the adhesive strength was measured again.

  As the paper feeding suitability, the number of jams (the number of jams) that occurred when 10,000 sheets were fed was measured.

The effect of removing paper dust or the like was confirmed by measuring the ratio of the area to which paper dust or the like adhered in 1 m ² of the surface rubber layer of the dust removal blanket after feeding 10,000 sheets. A surface rubber layer with a surface area of 1 m ² that has a paper dust adhesion area of 80% or more is large (symbol: double circle), 50% to less than 80% is round, and 10% to less than 50% Triangles and less than 10% were displayed as minimal (symbol: cross). In Comparative Examples 3, 4, 7, and 8, the number of jams was too large, and the paper dust / foreign matter removal effect could not be confirmed.

Regarding the peeling of the adhesive layer, after removing the dust with the dust removing blanket, the surface of the printing medium X sent to the paper discharge unit 24 is visually observed, and the surface rubber layer and the adhesive peeled off adhere to the printing medium X. Confirmed whether or not.

As is clear from Table 1, the dust removal blankets of Examples 1 to 4 have a high effect of removing paper dust and the like, have no jams, and have paper feeding suitability. After washing, the adhesive strength reaches the initial level. It recovers and can be used repeatedly by washing. Further, no peeling transition of the surface rubber layer to the re-paper was observed. On the other hand, according to Comparative Example 1 in which the adhesive strength with respect to the printing medium is less than 1 mN / cm, although it has paper feeding suitability, the effect of removing paper dust and the like was inferior. Further, according to Comparative Example 2 in which the adhesive strength with respect to the printing medium exceeds 500 mN / cm, the number of jams is large, and there is a problem in paper feeding aptitude. On the other hand, according to the pressure-sensitive adhesive sheets of Comparative Examples 3 and 4, since the pressure-sensitive adhesive strength to the printing medium (paper renewal) was too high, the paper renewal adhered strongly to the pressure-sensitive adhesive, resulting in tearing. Furthermore, according to the pressure-sensitive adhesive sheets of Comparative Examples 3 and 4, due to strong adhesion, the pressure-sensitive adhesive peeled off and transferred to the printing medium (added paper), and the printing medium became unsuitable for printing. In addition, a piece of paper or the like was entangled on the surface of the pressure-sensitive adhesive sheet of Comparative Examples 3 and 4, and remained after cleaning with the pressure-sensitive adhesive roller, and could not be reused after cleaning. Further, the adhesive peeled off during cleaning with the adhesive roller.

  As is clear from Table 2, the dust removal blankets of Examples 5 to 8 are excellent in the removal effect of paper dust and the like, have a small number of jams and have paper feeding suitability, and recover the adhesive strength to the initial level after washing. However, it can be used repeatedly by washing. Moreover, the peeling transition of the surface rubber layer to PET film was not seen. The removal effect of paper dust and the like in Examples 5 to 8 is a circle, because the removal effect is not inferior to that in Examples 1 to 4, and the generation of foreign matter from the PET film itself is less than that in the renewed paper. Please note that. On the other hand, according to Comparative Example 5 in which the adhesive strength with respect to the printing medium is less than 1 mN / cm, although it has paper feeding suitability, the effect of removing paper dust and the like was inferior. Further, according to Comparative Example 6 in which the adhesive strength with respect to the printing medium exceeds 500 mN / cm, there was a large number of jams, and there was a problem in paper feeding suitability. On the other hand, according to the pressure-sensitive adhesive sheets of Comparative Examples 7 and 8, since the pressure-sensitive adhesive strength to the printing medium (PET film) was too high, the PET film adhered strongly to the pressure-sensitive adhesive, and as a result, it was torn. Furthermore, according to the pressure-sensitive adhesive sheets of Comparative Examples 7 and 8, due to strong adhesion, the pressure-sensitive adhesive peeled off and transferred to the printing medium (PET film), making the printing medium unsuitable for printing. In addition, a piece of paper or the like entangled on the surface of the pressure-sensitive adhesive sheets of Comparative Examples 7 and 8, remained after cleaning with the pressure-sensitive adhesive roller, and could not be reused after cleaning. Further, the adhesive peeled off during cleaning with the adhesive roller.

DESCRIPTION OF SYMBOLS 1 ... Dust removal blanket for printing, 2 ... Support body layer, 3 ... Surface rubber layer, 4 ... Cotton cloth (first base fabric layer), 5 ... NBR adhesion layer, 6 ... Compression layer (NBR porous layer which mix | blended microballoon) ), 7 ... NBR adhesive layer, 8 ... cotton cloth (second base fabric layer), 9 ... NBR adhesive layer, 10 ... NBR solid layer, 11 ... NBR adhesive layer, 12 ... cotton cloth (third base fabric layer), 20 ... Multi-color printer, 21 ... paper feed unit, 22 ... dust removal unit, 23 ... printing unit, 24 ... paper discharge unit, 25a, 25b ... dust removal blanket cylinder, 26 _{1 to} 26 ₄ ... printing unit, 27a, 27b ... printing Blanket cylinder, 28a, 28b ... plate cylinder.

Claims (3)

A dust removal blanket for printing that removes dust adhering to a print medium by contacting the print medium before printing,
A surface rubber layer having an adhesive strength of 1 to 500 mN / cm with respect to the printing medium;
And a support layer for supporting the surface rubber layer , wherein the support layer includes a base fabric layer and a compression layer .   The dust removing blanket for printing according to claim 1, wherein the adhesive strength is in a range of 1 mN / cm or more and less than 200 mN / cm. The said support body layer is provided with the base fabric layer, the compression layer, the base fabric layer, the solid layer, and the base fabric layer which were sequentially arrange | positioned at the back surface side of the said surface rubber layer, The Claim 1 or 2 characterized by the above-mentioned. Dust blanket for printing.

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