JPH1119574A - Wetting water feed roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wetting water feed roller which can be easily maintained in good working condition by improving the durability and contact properties of a cloth for the roller. SOLUTION: In the wetting water feed roller for offset printing, the surface of a roller material 1 is covered with a tubular cloth 2 of ultraextremely fine fiber produced by knitting an ultraextremely fine yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply roller of a dampening water device for supplying water onto a printing plate for offset printing.

[0002]

2. Description of the Related Art Conventionally, offset printing plates have been supplied with dampening water so that ink is not received in hydrophilic non-image areas so that a resistance screen is formed for lipophilic ink. A water-absorbing roller called a water rod is used for supplying dampening water.

FIG. 6 shows a well-known dampening device for offset printing, in which a brass or chromium immersed in a pan 21 containing a dampening solution 20, or a water roller 22 coated on a cloth. A doctor roller 23 coated with a water-absorbent cloth intermittently in contact with the water roller 22, a metallic transfer roller 24 transferred from the doctor roller 23, and a surface from the transfer roller 24. Two damper rollers 2 that transfer the dampening solution uniformly spread over the entire surface of the plate and transferred by contacting the plate surface 25 continuously.
6 and the dampening water 20 transferred from the roller 22 for water is uniformly supplied to the plate surface 25 by using the rollers 23, 24 and 26.

[0004] The doctor roller 23 and the setting roller 26 are water supply rollers called water rods, and the surfaces of these rollers are referred to as moltons in the industry so that a proper amount of dampening water can be absorbed and supplied. Using a water-absorbent cloth band, the roller is flatly wound around the body of the roller or covered with a cloth cylinder.

[0005] The water-absorbing cloth used for the water bar is designed so that water can be absorbed and supplied to form a good dampening curtain on the plate surface.
It is a velvet made by cutting loops on the surface of a fiber woven in a pile shape, and the surface of the cloth is dense and smooth, has high uniformity, and has improved water absorption and water retention.

[0006]

However, since the conventional cloth for a water rod is formed by cutting a loop, it has a large amount of fluff and fluff, and is liable to cause thread breakage and breakage. Had been lowered. In addition, if these lints adhere to the surface of the plate or the inking unit, they cause damage to the printed pattern. Therefore, it takes a long time to carry out operations such as removing lint before using a new roller, and requires a great deal of attention in managing the cloth on the roller surface. In addition, the conventional operation of winding a water-absorbing cloth around the body of a roller requires skill, and replacing a dirty or worn cloth is troublesome for an unskilled worker.

The present invention has been made in view of the above problems, and can improve the durability of a cloth for a water supply roller and maintain the proper damping state by increasing the contact of the roller with the plate surface. The purpose is to make maintenance easy.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a roller for supplying dampening water for offset printing, wherein the surface of the roller body is made of ultra-fine fibers knitted and woven with ultra-fine fibers. Covered with body.

Further, since the tubular cloth body is formed of ultra-fine fibers woven in a loop shape, it is difficult to unravel the yarn or to remove the yarn, it is soft and has good water absorption with good contact with the plate surface. A water supply roller excellent in water retention can be obtained.

By forming the tubular cloth body seamlessly by knitting, the uniformity of the roller surface is improved, and the contact with the plate surface is further improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 to 5 show an embodiment of a dampening water supply roller according to the present invention, which is used for a dipping roller or a doctor roller for supplying dampening water to a plate surface of offset printing. It is composed of a known roller body 1 and a tubular cloth body 2 made of cloth that covers the roller body 1.

The tubular cloth 2 is mainly made of acrylic, polyester, polyamide, or a blend of 0.1 to 0.1.
Pile knitting, shown in FIG.
That is, the knitted fabric is knitted in a loop shape and formed as a super-fine fiber into a seamless elastic tube (see FIG. 3).

The ultra-fine fibers knitted by the ultra-fine yarns have a three-dimensional structure having a high porosity, and the impregnation rate of the dampening solution is higher than that of a conventional water-absorbing velvet cloth called "Morton" in the industry. Fountain solution is high, and the dampening solution is well retained based on the capillary action due to the ultrafine yarn.

The ultra-fine fibers used in the tubular cloth body 2 are not broken and the thread hardly breaks because the loops are not cut, and are more durable than the conventional water-absorbing cloth. It is a water supply cloth suitable for offset printing dampening work with less generation of fluff and fluff.

When the tubular cloth body 2 is put on the roller body 1, the elasticity of the tubular cloth body 2 makes close contact with the body peripheral surface of the roller body 1, and is covered without twisting or looseness of the cloth, so that water can be supplied to the plate surface well. Form a soft and smooth roller surface.

Further, the tubular cloth body 1 has a high contact property to the plate surface due to the characteristics of the ultra-fine fibers of the ultra-fine fibers, and further has no seams, so that the roller surface is excellent in uniformity and the plate surface is not uneven. Can form a resistance curtain against the ink by the dampening water in the state of (1).

The tubular cloth body 1 coated on the roller body 1 is
The opening 4 is narrowed by the tightening cords 3 at both ends thereof, so that the opening 4 is detachably fixed.

Therefore, when the tubular cloth body 2 is worn or damaged, its replacement is easy, and the installation does not require the skill of winding a conventional water-absorbing cloth on a roller. In addition, when soiled, it can be washed and reused, which is economical.

The method of knitting the ultrafine fibers is not limited to the knitting, but as shown in FIG. 5, the bristle is raised to form a moquette (a state in which the bristle is raised vertically). The ultra-fine fibers may be formed into a tubular body to form a tubular cloth body, and can have almost the same functions as those of the above embodiment.

[0021]

The present invention is embodied in the form described above and has the following effects.

Since the surface of the roller body is covered with a tubular cloth body made of ultra-fine fibers knitted with ultra-fine yarns, the elasticity of the tubular cloth body makes a close contact with the body peripheral surface of the roller body, so that the conventional water supply roller is used. As a result, a smooth roller surface having extremely high water absorption and water retention is formed.

The roller surface is soft and uniform because the tubular cloth body is formed seamlessly with loop-shaped superfine fibers so that the surface of the roller is in contact with the plate surface because of the properties of the superfine yarn. The resistance is extremely dense, and a resistance curtain made of a dampening solution in the best condition without unevenness on the plate surface can be formed.

The ultra-fine fibers woven in a loop form have less fluff and fluff and less thread breakage. Therefore, the maintenance time before using a new water supply roller can be shortened, and the durability is excellent and it is economical.

Furthermore, since the tubular cloth body can be easily attached to and detached from the roller body, it is a roller for water supply that does not require any skill in replacement work when it is damaged or becomes dirty, and is easy to maintain.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a roller for supplying dampening water according to the present invention.

FIG. 2 is an enlarged sectional view taken along the line XX of FIG. 1;

FIG. 3 is a perspective view of a tubular cloth body of the roller of FIG. 1;

FIG. 4 is an enlarged view for explaining ultra-fine fibers used in the present invention.

FIG. 5 is an enlarged explanatory view showing another embodiment of the ultrafine fiber used in the present invention.

FIG. 6 is an explanatory view showing a conventional dampening device.

[Explanation of symbols]

 1 roller body, 2 tubular cloth body,

Claims (3)

[Claims] 1. A dampening water supply roller for offset printing, wherein the surface of the roller body is covered with a tubular cloth body made of super-fine fibers woven by super-fine fibers. roller. 2. A dampening water supply roller according to claim 1, wherein the tubular cloth body is formed of ultra-fine fibers woven in a loop. 3. The roller for supplying dampening water according to claim 1, wherein the tubular cloth body is formed seamlessly by knitting.