AU619383B2

AU619383B2 - Inking arrangement for printing machines

Info

Publication number: AU619383B2
Application number: AU49198/90A
Authority: AU
Inventors: Yuichi Okamura
Original assignee: Tokyo Kikai Seisakusho Co Ltd
Current assignee: Tokyo Kikai Seisakusho Co Ltd
Priority date: 1989-02-10
Filing date: 1990-02-07
Publication date: 1992-01-23
Anticipated expiration: 2010-02-07
Also published as: CA2008615C; ATE115046T1; DE69014670D1; EP0382572B1; JPH0822591B2; DE69014670T2; JPH02209243A; EP0382572A3; CA2008615A1; EP0382572A2; AU4919890A

Abstract

An inking arrangement for printing machines in which ink is supplied to the plate surface by means of ink form rollers (5). The inking arrangement comprises a roller train constituted of a plurality of rollers (2,3,4,5) each having its surface layer made of a single non-metallic material (S) or a mixed material containing a non-metallic material as a base material (T), the rollers (2,3,4,5) being successively arranged in contact with or in close proximity to each other. Thus, it is possible to obtain an excellent ink transfer condition and hence possible to prevent occurrence of the roller stripping phenomenon, which is likely to occur in an offset printing process, for example.

Description

COMMONWEALTH OF AUSTRALIA 1 383 PATENTS ACT 1952 Form COM~PLETE SPECIFICATION FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: 0s *0 *000 0*0* 000* 0 0 Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT *0 Name of Applicant: TOKYO KIKAI SEISAKUSHO, LTD.

Address of Applicant: 26-24, Shiba 5-chome, Minato-ku, TOKYO,

JAPAN

Actual Inventor: Yuichi Okamura Address for Service: GRIFFITH HACK CO 71 YORK STREET SYDNEY NSW 2000 Complete Specification for the invention entitled: INKING ARRANGEMENT FOR PRINTING MACHINES The following statement is a full description of this invention, including the best method of performing it known to us:- 20690-E:COS:RK 3668A:rk -2

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"INKING ARRANGEMENT FOR PRINTING MACHINES" Field of the Invention The present invention relates to an inking arrangement for use in printing machines and, more particularly, to an inking arrangement in which ink is supplied to the printing plate surface by means of ink form rollers.

Description of the Prior Art A typical conventional inking arrangement in which ink .0 is supplied to the plate surface by means of ink form rollers comprises two different kinds of rollers which are alternately disposed in contact with or in close proximity to each other. One of the two being a metallic roller having its outer peripheral surface made of a metallic material, and the other being a rubber roller having its outer peripheral surface made of a rubber material. For example, see A' Guide to Printing Machines, by Akitoshi Watanabe. Publishing Section of Printing Society, first impression/first edition, July 1, 1985, lines 1 to 2, page iO The above-described prior art suffers, however, from the following problem.

The ink receiving ability of the metallic roller having its outer peripheral surface made of a metallic material may deteriorate during the printing operation, resulting in insufficient supply of ink to the printing surface.

Deterioration of the ink receiving ability leads to a roller stripping phenomenon in which the metallic outer peripheral surface of the roller is exposed due to a failure 30 in transfer of ink.

3 S:20690E I A 3 Summary of the Invention It is a primary object of the present invention to provide an inking arrangement for printing machines which is free from the problem caused by deterioration of metallic rollers.

To this end, the present invention provides an inking device for printing machines including a roller train comprising a plurality of rollers successively arranged, and each in close proximity to the adjacent roller or rollers, 10 in the succession; wherein the surface layer of each of the 0 99 rollers of the train comprises a non-metallic, ink receiving material.

Preferably at least two successive rollers of the train are arranged in contact with each other.

Preferably the non-metallic material is an oleophilic material.

Preferably the non-metallic material is a resin or a synthetic resin.

Preferably the non-metallic material is a urethane 20 resin, nitrile butadiene rubber, polychloroprene rubber or

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S natural rubber.

Preferably the non-metallic material includes minute hollow bodies. Optionally the minute hollow bodies are microballoons, microspheres, hollow bubbles or synthetic foam. Advantageously the minute hollow bodies have a diameter within the range 5um to 300jm. Also advantageously the minute hollow bodies at the surface of the surface layer are open such that ink is retained in the hollow portion.

Preferably the non-metallic material includes a powder of a hard material. Optionally the hard material is a ceramic or metallic material. Advantageously the particle A size of the powder is within the range lim to 100m.

L- _r ii i i L a~ ~-FI sl-UOP-rY -4 The rollers constituting the roller train in the inking arrangement rotate in their respective directions, i.e.

alternate rollers rotate in the same direction, to supply ink from an ink furnishing device to a printing plate fitted to the outer peripheral surface of a plate cylinder by the successive ink transfer operation.

Since the surface layer of each roller is made up of either entirely of a non-metallic, ink receiving material, or a mixed material containing such a non-metallic material 10 as a base material, it is possible to obtain excellent ink e transfer and hence possible to prevent occurrence of the roller stripping phenomenon, which is likely to occur in offset printing process, for example.

Brief Description of the Drawings The above and other objects, features and advantages of the present invention will become more apparent from the following description of the preferred embodiment thereof, taken in conjunction with the accompanying drawings, in which like reference numerals denote like elements, and of 00 which: 0 Figs. 1(a) to l(e) are schematic views of inking arrangements for printing machines according to one embodiment of the present invention which have various ink furnishing devices, respectively; Fig. 2 is a schematic view showing a modification to a roller train arrangement in an embodiment of the inking arrangement for printing machines according to the present invention; and Figs. 3(a) to 3(g) are schematic views of inking arrangements for printing machines according to an embodiment of the present invention which have various PL/j1,i blades, respectively.

S:20690E L. .1 C 1IIII Detailed Description of the Preferred Embodiment Referring to Figs. 1 to 3, the inking arrangement comprises an ink furnishing device 1 and a roller train constituted of an ink fountain roller 2, a second roller 3, a first roller 4 and ink form rollers 5 which are arranged in succession so as to rotate while being in contact with the neighbouring rollers at the respective outer peripheral surfaces.

The ink fountain roller 2 is supplied with ink from the ink furnishing device 1. The second roller 3 is supplied .6 with ink from the ink fountain roller 2 and transfers it to i* the first roller 4. The first roller 4 transfers the ink to two ink form rollers 5, 5 which are juxtaposed to each other. The ink form rollers 5, 5 rotate while being in contact at the outer peripheral surfaces with a printing plate fitted to the outer peripheral surface of a plate cylinder P, thereby transferring the ink supplied from the first roller 4 to the printing plate fitted on the plate cylinder P.

Figs. l(a) through l(e) exemplarily show inking arrangements having various ink furnishing devices 1, respectively.

The ink furnishing device 1 shown in Figs. l(a) is an S" ink fountain. The ink furnishing L ;1, devices 1 shown in Figs. l(b) and 1(e) are ink fountains in each of which at least a part of the opening thereof is divided by the ink fountain roller 2. The ink furnishing device 1 shown in Fig. 1 is an ink discharge body.

The ink furnishing device 1 shown in Fig. 1(d) is an ink rail having an ink pump IP.

Each of the rollers, i. e. the ink fountain roller 2, the second roller 3, the first roller 4 and the ink form rollers 5, has either a surface layer S made of a non-metallic material or a surface layer T made of a mixed material containing a non-metallic material as 0:0 a base material. Table below shows possible combinations of two different kinds of rollers, that is, the one having the surface layer S and the other having the surface layer T, to constitute a roller train.

*The above-mentioned non-metallic material preferably has excellent ink receiving ability, and when the ink used is an oil-baszd one, an oleophilic and oil-resistant non-metallic material is preferably employed. Examples of non-metallic materials usable in the present invention include synthetic resins such as urethane resins, nitrile butadiene rubber (NBR) and polychloroprene rubber (CR) and resins such as natural rubber (NR) and so forth.

i 1 Table *c *0*0 0 0 00 0 *000 0 0**0 0000 0 00*0 000* 0 0* 0 Ink fountain Second First Ink form roller roller roller rollers a S S S S b T S S S c S T S S d S S T S e S S S T f T T S S g T S T S h T S S T i T T T S j T T S T k T T T T 1 S T T S m S T S T n S T T T o S S T T An example of the above-mentioned mixed material that contains a non-metallic material as a base material is a composition formed by substantially uniformly dispersing and mixing, singly or in combination of more than one material, minute hollow bodies and/or the powder of a hard material in a urethane resin, for example. The minute hollow bodies are generally called microballoons, microspheres, hollow bubbles, or synthetic foam. It is possible to use minute hollow bodies which have a particle diameter in the range of about to about 300pm, at least. As to the powder of r 3~L~CIPl~i~.~~ a hard material, it is possible to use a ceramic or metallic powder having a particle diameter in the range of about lim to about lO00m, at least. The size and mixing ratio of components of the mixed material may be properly selected.

Although in the arrangement shown in Fig.

1 the ink fountain roller 2 and the second roller 3 are inn contact with each other, these two rollers may be disposed in close proximity to each other with a proper gap provided therebetween, as shown in Fig. 2. The arrangement may also be such that the second roller 3 is pivotally provided so as to alternately come into contact with the ink fountain roller 2 and the first roller 4, although this alternative arrangement is not s own.

Figs. 3(a) to 3(g) exemplarily show various combinations of the inking arrangement shown in Fig. 1 with various blades.

A doctor blade 6 that removes an excess of ink supplied onto the second roller 3, an ink film thickness regulating blade 7 that regulates the thickness of ink film on the ink fountain roller 2 and an ink film thickness flatting blade 8 that makes uniform the thickness of ink film on the first roller 4 are properly combined with the roller train and disposed in opposing relation to the associated rollers.

The inking arrangement including blades is not necessarily limited to that shown in Fig.

-t-7- Blades can be applied to any of the aforementioned inking arrangements comprising various combinations of rollers.

The ink fountain roller 2, the second roller 3 and the first roller 4 in the inking arrangement may be properly driven by either the same driving system or respective driving means. The peripheral speeds of these rollers need not be the same.

•r The following is a description of the operation of the above-described inking arrangement.

The ink fountain roller 2, the second roller 3, the first roller 4, the ink form rollers 5, 5 and the plate cylinder P rotate in their respective directions, alternate rollers rotate in the same direction, so that the ink which is supplied from the ink 00..

furnishing device 1 to the ink fountain roller 2 is effectively transferred from the roller 2 to the second roller 3, the first roller 4 and the ink form rollers 5, 5 in succession with the ink film thickness being properly regulated, and it is further transferred from the ink form rollers 5, 5 to the printing plate fitted on the plate cylinder P.

Since each roller has either a surface layer S made of a non-metallic material which has excellent ink receiving ability or a surface layer T made of a mixed material containing such a non-metallic material as a base material, it is possible to obtain an excellent ink transfer condition and hence i I- ~CC u~na, possible to prevent occurrence of the roller stripping phenomenon, which is likely to occur during offset printing process, for example.

In the case where each roller has a surface layer made of a mixed material having minute hollow bodies dispersed and mixed therein, part of the shell layer of each minute hollow body on the outer peripheral surface of the roller is removed to open the hollow portion. Accordingly, the opened hollow bodies positively retain the ink transferred from the upstream side and transfer it to the downstream side. Therefore, this arrangement is even more preferable from the viewpoint of preventing failure in transfer of ink.

In the case where each roller has a surface layer made of a mixed material having the powder of a hard material dispersed and mixed therein, the hard material powder that is a component of the mixture bears the friction acting on the roller. Accordingly, if this arrangement is used when the doctor blade 6 or the ink film thickness flatting blade 7 is used 9 in contact with the outer peripheral surface of a roller or when one or more of the ink fountain roller 2, the second roller 3 and the first roller 4 are different from the rest in the peripheral speed, the wear of the outer peripheral surfaces of the rollers can be effectively suppressed. Proper selection of a hard powder material and a mixing ratio of components of the mixture makes it possible to improve the thermal conductivity and also

L

I-k- 0 i 11 suppress generation of heat in operation.

Although the present invention has been described through specific terms, it should be noted that the described embodiments are not necessarily exclusive and that various changes and modifications may be imparted thereto without departing from the scope of the invention which is limited solely by the appended claims. For example, either one or both of the second and first rollers 3 and 4 may be removed from the roller train and/or the niumber of ink form rollers 5 may be increased or reduced.

o' Each roller has either a surface layer S made of a nonmetallic material which has excellent ink receiving ability or a surface layer T made of a mixed material containing °.eS such a non-metallic material as a base material. Therefore, 9*95 r o it is possible to obtain an excellent ink transfer condition and hence possible to prevent occurrence of the roller stripping phenomenon, which is likely to occur in offset OO 06O printing process, for example. Since an adequate amount of ink is supplied to the printing plate surface, it is *eS possible to continuously obtain prints of uniform quality oo and also reduce spoilage.

Further, it is possible to obtain a roller which has Ssurface properties conformable to each particular application and which is reasonable in cost by properly using a non-metallic material as a main component of the S:20690E z S :20690E r *gg S roller surface layer material.

In the case where each roller has a surface layer made of a mixed material containing a non-metallic material as a base material, the ink receiving ability and ink transfer ability of the outer peripheral surface of the roller can be suitably selected by properly selecting a base material and components of the mixture. In addition, by properly selecting constituent materials and mixing ratios of components of the mixture, it is possible to improve the wear resistance and thermal conductivity of the roller surface layer or add and regulate ink retaining ability with relative ease and at low cost.

Accordingly, it is possible to provide an inking arrangement free from insufficient supply of ink.

too 44

Claims

1. An inking device for printing machines including a roller train comprising a plurality of rollers successively arranged, and each in close proximity to the adjacent roller or rollers. in the succession; wherein the surface layer of each of the rollers of the train comprises a non-metallic, ink receiving material.

2. An inking device according to claim 1 wherein at least two successive rollers of the train are arranged in contact with each other.

3. An inking device according to claim 1 or 2 wherein the non-metallic material is an oleophilic material. 0

4. An inking device according to claim 1, 2 or 3 wherein the non-metallic material is a resin or a synthetic 15 resin.

An inking device according to any one of claims 1 to 4 wherein the non-metallic material is a urethane resin, nitrile butadiene rubber, polychloroprene rubber or natural rubber.

6. An inking device according to any preceding claim 0 wherein the non-metallic material includes minute hollow bodies. e

7. An inking device according to claim 6 wherein the minute hollow bodies are microballoons, microspheres, hollow bubbles or synthetic foam.

8. An inking device according to claim 6 or 7 wherein the minute hollow bodies have a diameter within the range to 300m. S 3:20690E 1 I -i 14

9. An inking device according to claim 6, 7 or 8 wherein the minute hollow bodies at the surface of the surface layer are open such that ink is retained in the hollow portion.

10. An inking device according to any preceding claim wherein the non-metallic material includes a powder of a hard material.

11. An inking device according to claim 10 wherein the hard material is a ceramic or metallic material.

12. An inking device according to claim 10 or 11 wherein the particle size of the powder is within the range 1pm to 100Am.

13. An inking device substantially as hereinbefore described with reference to the accompanying drawings. DATED this 22nd day of October 1991 TOKYO KIKAI SEISAKUSHO, LTD. By their Patent Attorneys GRIFFITH HACK CO. *S Jk