JPS58220751A - Removal of picking from printing face of printer - Google Patents

Abstract

PURPOSE:To remove picking from the printing face of a printer by a picking manner by a method in which a roll covered with a pile structure consisting of the back texture of a hydrophilic fiber and cut piles of hydrophilic and/or oil- repellent fiber is contacted with the printing face while supplying water to the roll. CONSTITUTION:A picking roll 1, while being supplied with water, is contacted with the printing face before an inking roll. The surface of the picking roll 1 is covered with a pile structure 2 with uprising piles 5 of a hydrophilic and/or oil- repellent fiber, and the back texture of the pile structure 2 is made up of a hydrophilic fiber. A picking is moved to the picking roll in such a way that it thrust into the pile fibers and is absorbed into the inside of the pile structure. Thus, the adhesion of ink and picking can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for removing adhering foreign matter such as fragments of dried ink, paper dust from printing paper, hair scraps from water stick rolls, and dust floating in a factory from the plate surface of a printing press, that is, dust. It is related to.

Hitsuki adhering to the plate surface can cause problems when the ink is not transferred to the printing surface of the printed matter, causing minute white spots, and the printing plate must be cleaned by periodically stopping during continuous printing to remove the hitskis. is necessary.

However, cleaning the plate while stopping the plate not only leads to a decrease in the operating rate, but also causes the cleaning marks left on the plate to completely transfer to the printed matter and disappear from the plate when printing is restarted after cleaning. Since defective printed matter with the cleaning traces transferred thereto is used, there is the disadvantage that the printing burden is reduced.

The picking roll picks up the keys that are transferred to the printed matter.
It is transferred to the surface of the roll and removed, and is used in contact with the plate surface at all times or whenever picky is discovered, thereby eliminating the inconvenience caused by cleaning the plate surface. Therefore, in the picking roll,
A material with a rough surface to which heat transfer is easier than printing paper is used, and rolls wrapped with Molton and @3
A method has been proposed in which a roll with fiber fluff on the surface, such as a rubber roll with fiber pieces wrapped around it and a machined surface, is used instead of a part of the roll for inking.

However, the use of conventional picking rolls has the following problems.

(1) Mixing the rubber or resin elastomer composition with the fiber pieces makes the rubber roll "hard", so it is impossible to mix in a large amount of the fiber pieces, and the surface is cut and polished. The fiber naps that appear protruding from the surface are less than 1%, so to speak, on the micron level, and both the rubber roll kneaded with fiber pieces and the roll wrapped with Molton stand upright on the roll surface, and the protruding ratio of nine naps is small, making it easy to use. Since the stickies adhering inside the roll stick together with the ink and smooth the roll surface, a sufficient hitkki removal effect cannot be expected.

(2) For rolls wrapped with Molton, which does not stand upright but lies diagonally and has a lot of fluff on the surface that gets entangled with the base fibers, the stickies that adhere to it during use are thrown onto the fluffy fibers that lie down, along with the ink. Since it buries and sticks, it is difficult to remove even by washing, and the ink from the previous control remaining after washing oozes out during reuse, resulting in defective prints when printing starts after cleaning and reusing the picking roll. be done.

(3) Because it is difficult to clean the reusable container, it is necessary to stock up on replacement picking rolls, and therefore a special storage space must be provided within the factory.

(4) For rubber rolls mixed with knowledge fiber pieces,
It is almost impossible to use it.

(5) The use of a picking roll instead of a part of the roll for ink application is to rub the ink that remains on the ink-attached handle part of the printing plate after transferring it to the blanket cylinder or printing paper package and eat it out of the outline. Because the ink oozes out, the outline of the ink-attached handle is subtended, making it impossible to obtain clear printed matter.

The present invention solves such inconveniences, and uses a pile Sakaki structure consisting of a lining structure made of hydrophilic fibers, a surface pile made of hydrophilic and/or oleaginous fibers with cut ends, and K. The gist of the inking is to bring a roll coated with upright pile naps into contact with the plate surface while applying moisture at the front end of the roll (0111).

The present invention will be explained below with reference to the illustrated embodiments.
The figure is a schematic side view of a printing press. and is further transferred to the printing paper 15 via the blanket cylinder 14. A water wetting roll 16 is attached to the plate cylinder 13. A water rod 19 to which water 18 has been applied via the chrome roll 17 comes into contact with the printing plate to apply moisture to the plate surface. In addition, 20 in the figure is an impression cylinder.

The picking roll and the plate cylinder may be such that the tip of the pile lightly touches the plate surface.

According to the conventional example, the picking roll is installed in place of the inked roll 12 that first comes into contact with the printing plate, but in the embodiment of the present invention, the picking roll is installed at the position where the inked roll first contacts the printing plate, but in the embodiment of the present invention, the picking roll is installed at a position that is closer to the rotational direction N of the printing plate than the water rod roll 19. Furthermore, there is a chrome roll on the front side]
7 and the plate cylinder.

Therefore, the surface of the picking roll 1 is wet with water.

The picking roll l in the embodiment is composed of a roll base body 3 and a cylindrical cover 2 made by knitting machine Ii, as shown enlarged in FIG. 2, and the cover 2 has a lining structure (base).
4 and base 4, and one pile 5 stands upright on base 4.
It is made up of.

Hydrophilic fibers such as cotton, hemp, rayon, acetate, cupro, and polyvinyl alcohol (vinylon) are used for the lining fabric. In this case, hydrophobic N1. Kasuri may be used in combination. These #l! As is clear from the example of fibers (in the present invention, "M aqueous #
"I fiber" refers to fibers that are easily wetted by water and have the property of retaining water absorbed between the fibers when aggregates of these fibers, such as threads, fabrics, and webs, become wet and are usually referred to as "hydrophobic fibers". It does not include nylon, polyester, polyvinyl chloride, polyvinylidene chloride, acrylic wire, etc.

Among the above-mentioned hydrophilic fibers, strong rayon with a large degree of extension and non-acetalized or low-acetalized polyvinyl alcohol fiber especially absorb moisture and shrink, so the texture of the cylindrical cover 2 as shown in FIG. When the cover 4 is made of these fibers and is stretched low to the roll body 3 and then moisturized, the cover 2 will come into close contact with the roll body 3 due to water contraction of the ground tissue.
It is convenient for the production of the picking roll 1, and for this purpose it is particularly recommended to use un- or acetalized polyvinyl alcohol fibers which exhibit a water shrinkage of 10% or more.

For the pile, in addition to hydrophilic fibers, fluorine-based synthetic fibers such as oil-propelled twill fibers such as tetrafluoroethylene (Teflon) fibers can also be used.

Pile structures made of such lining fibers and piles can be produced using not only the above-mentioned circular knitting machines but also tricot knitting machines, raschel knitting machines,
M, ', ',..., pupile fabric with ring-shaped piles is produced by weaving a pile fabric with a total pile yarn denier of 600 to 700 deniers, such as a moquette loom or a towel loom. The loop pile can also be sheared and used as cut pile by cutting the tip of the loop pile.In this case, using filament yarn instead of spun yarn as the pile yarn makes the present invention even more effective. Probably.

P What you should pay particular attention to here is the thickness of the pile fiber (single yarn denier) and the protruding length of the pile (pile length). , more preferably using fibers of 5 to 10 denier,
The pile length is 1 to 5I6, preferably around 21%. This is because when a picking roll with a single yarn denier of 2 deniers or less and a pile length of less than 11 denier is installed in contact with the chrome roll 17 together with the water rod roll 19 as shown in FIG. As with a simple dampening device equipped with two water rod rolls, no hitch removal effect is expected, and the single yarn denier is 50 to 10.
This is because if the denier is set to 0, the plate surface will be easily worn and the useful life will be shortened.At the same time, piles of 100 denier or more are rigid at the base and have poor entanglement with the ground structure, making them difficult to install before being attached to the roll body 3. Depending on how you handle it, it can easily cause hair loss. However, the single yarn denier of pile fibers is such that many pile fibers on the surface of the Morton picking roll stand upright and are close to each other, so they transfer to the picking roll in a manner that pierces between the pile fibers. Then, when it comes into contact with the hit key attached to the plate surface in this way and grips it between the pile fibers that are in close contact with each other, as if picking it up, and then overlaps the VC and grips the hit key, the tip key is absorbed into the inside of the pile structure. Therefore, the hit key removal effect does not deteriorate during continuous printing retreat. This absorbent action is caused by the fact that the pile is made of hydrophilic or oil-repellent fibers, which retain water between the fibers when water is added to them, and the pile fibers are not stuck to the pile fibers but are placed in a floating state between the pile fibers. This is thought to be due to absorption, but in the present invention, not only the pile but also the lining fibers are made of hydrophilic #J1 fibers,
Because it absorbs water and moisture and becomes oil-repellent, it repels ink.
Ink and bottle keys do not stick to each other, and therefore, it is easy to clean and remove the transferred and absorbed stickies after printing is completed.Especially when changing ink colors, since the picking roll is in a wet state where ink does not adhere. It is not always necessary to replace or clean the picking roll, and work such as replacing or changing colors can be streamlined.

At the same time, the pile structure is attached to the replaceable roll body, so the roll body can be removed for replacement, and the pile structure required for replacement can be folded and stored, making it possible to store one roll. Being inexpensive compared to the main body, the implementation of the present invention is extremely economical.

The picking roll 1, which is attached to the front side of the ink roll under water pressure, also has the function of coating water onto the plate surface in the same way as the water dispenser o-le [7]. When the picking roll 1 is attached to the front side of the stick roll 19, the ink 23 that has been transferred to the blanket cylinder 14 and still remains slightly on the ink-attached handle 22 is removed by contact with the tip of the pile of the upright picking roll. Even if the ink 23 oozes out from the handle contour to the plate surface area 21, the ink 23 that oozes out due to the water that is subsequently applied from the water rod roll 19 to the plate surface area 21 will be pushed out again due to surface tension. Since it is pushed back into the outline of the handle, it is printed more clearly than before.

Furthermore, the pile structure 2 wound around the roll body 3 is
Since the base structure is a hydrophilic fiber that shows water shrinkage, even if it is formed as a cylindrical cover as shown in Fig. 2 and is simply attached to the roll body 3 with low elongation, during use. It does not slip off from the roll body 3, but on the contrary is tightened by the applied moisture and tightly adheres to the roll body.

Such water contraction of the ground structure increases the pile density of the woven wire diameter, and also acts to maintain the upright state by bringing each pile fiber closer together and erecting each other. As a result, the hitkey gripping and absorbing ability is further increased, making hitkey removal even more effective.

Similarly, the embodiment of the present invention illustrates a case where water is applied to the picking roll 1 by a dampening device, but this picking roll 1 is made independent from the dampening device and moisture is applied by a spray device or the like. Also, it can be installed anywhere in front of the ink roll, regardless of whether it is in front of or behind the water rod roll, or even if the contact between the picking roll 1 and the plate cylinder 13 is intermittent. Therefore, the present invention includes these embodiments, and the technical scope of the present invention is not reduced or limited thereby.

[Brief Description of the Drawings] Figure 1 is a side view of a printing press according to an embodiment of the present invention, Figure 2 is a partial sectional view of a picking roll according to the present invention, and Figure 3 is a partial perspective view of a printing plate. It is. l... Picking roll 2... Pile structure 3... Roll body 4... Ground structure 5... Pile 9', 10.11.12... Roll 13 with ink
...Plate body] 8...Water patent applicant Technoroll Co., Ltd. agent Patent attorney (Fl] 89) Shigeo Chiba 3rd day

Claims (1)

[Claims] A roll whose surface is covered with a pile structure consisting of a lining structure made of hydrophilic fibers and a surface pile made of hydrophilic or oleaginous fibers with cut ends is placed on the front side of the roll for inking. A method for removing stains from a plate surface in a printing press, the method comprising contacting the plate surface while applying moisture.