The published articles are meant to primarily educate the students in printing to supplement their knowledge in the field of Printing. These are not simple Glossary of printing terms, but to the extent possible every term has been explained in brief so that it can be of some use to the students who appear in some sort of examinations and interviews.
I served the Printing Industry for over 40 years
in various capacities, a major part in an Security Printing Organization. In order not to waste the printing and paper related knowledge which I gained over years, I decided to keep them in public domain for the reason stated in prepara. Most of the illustrations - over 90% - have been generated by me to explain the terms suitably.
While I am not sure to what extent the published content will help, if the content is going to be of use to some one in some manner, I will be greatly satisfied.
Your views may be sent to me (
nrj_1945@yahoo.com) for my record and correction wherever needed.

TOTAL NO OF PRINTING TERMS

POSTED TILL NOVEMBER, 2012

- Over 400 terms-

Click on this line to read from 'A'

Saturday, June 28, 2014

PROCESS FREE PLATES FOR PRINTING


Recent Developments
 in Printing Series- 5
 
PROCESSFREE    PLATES  

 FOR   PRINTING
(N.R. Jayaraman)


In  1960s, as an improvement in the conventional Plate making technique in which the plates used to be coated with a light sensitive solution on a whirler, dried and then exposed, a modified plate making technique called 'wipe-on' plate making system, wherein a ultra violet light sensitive liquid emulsion were hand coated with a sponge on to the plate and further processed instead of spreading and drying the sensitive emulsion on a whirler before final processing. 


Besides Wipe on coating, Pre -sensitized coated plates were also made available by some of the firms, especially by a firm called Technova Imaging Systems (now the firm is offering Digital Pint solutions and plates for various processes like CtP) , that reduced several of the intermediately process. These two processes in nutshell eliminated the use of whirler with heater for coating the plate.  The wipe on plates and the Pres sensitized plates were inexpensive and easily processed but in the case of wipe on plates it usually suffered from inconsistencies of emulsion thickness, because they were hand coated. Some of the plate innovations like process free plates offer unprecedented benefits for printers since both equipment and steps have been removed from plate making, thus streamlining the path from computer to press.

Further developments took shape in the field of Plate making (for printing by Offset , Letterpress, Flexo or Intaglio) with the introduction of CtPs (Computer to plates system) that eliminated several intermediately steps thus saving time and cost though the one time initial investment was heavy. For the presses that print volumes and varieties through the year, with supplies to be made in short time span, the CtPs were a boon. However much smaller units could not afford the CtPs. The development in Plate making /Printing took further leap with the introduction of Digital technology  (Also read : Recent Developments) which totally eliminated plate making and direct print on any surface through either Letterpress or Flexo or by Offset machines was made possible. However the Digital printing too had its own limitations in the application of printing volumes and fine arts. Thus it became evident that the Plate making process in some manner or the other for making plates to print by Offset, Letterpress, Gravure, Intaglio or Flexo cannot be altogether eliminated.  However it was realized  that some alternate technology  could be devised to reduce the processing of the Plates meant for printing through  the machines.

In the recent years there has been emergence of several Plate making techniques/ systems developed by few firms. One interesting development that has emerged has been the reconverting of uncoated, blank grained anodized aluminum plate into reusable plate i.e converting the plate from hydrophobic to hydrophilic state, so that they don’t need any re coating of aluminum at all and direct imaging is made possible. This process is applicable on anodized aluminum plates only which can be reused several times without going in for fresh anodizing process. Earlier the Anodized Alluminium plates once used were discarded as further  unserviceable plates or re anodized to make them reusable.  

As per the new invention, a carefully controlled femtosecond laser pulse coating modifies an aluminum oxide surface to create a highly hydrophilic imaged layer to accept images. According to the firm which has developed this technology named 'Miracle technology' claims that it does away with aluminum coatings and graining of plates processing entirely. (Read more information  in:  Miracle  Technology and  Verdigris project.com )
The benefits of this technology is the potential elimination of all chemicals in plate coating, organic solvents from the coating process, as well as all requirements for processing equipment and associated chemistry. It would also have major environmental benefits by drastically reducing the demand for aluminum within the printing industry. After use the plate is cleaned with a standard plate cleaner and reverts to its normal hydrophobic state. The Miracle technology has the potential to provide a re-writable surface which could in turn, provide a plate which could be reused several times.( http://miracle-plate.com/)

Another invention called CreoScitex "SP Plateless Technology" is a plate imaging system where a plate could be imaged, and re-imaged, by spraying an ink receptive coating (Agfa Lightspeed) on while the plate was still mounted on press. It would drastically cut down the quantum of manufacturing, cutting, and shipping new plates used for making printing plates.

' Plate less Digital Offset Printing called Agfa LiteSpeedis a patented lithographic coating liquid (US0603750,EP00849091,JP03122717) for application on-press and fully compatible with the CreoScitex SP ™ process. LiteSpeed offers new perspectives for high quality, short run length applications. ( Read more comments on the development in http://printplanet.com/forums/printing-industry-news/18670-miracle-plates )

On press, it is first sprayed onto a hydrophilic substrate, then imaged, and again cleaned after the print job is finished. LiteSpeed forms a thermally fusable coating :during imaging . Fine thermoplastic particles are fused together and sprayed onto the substrate to form the printing image. The technology is strongly related to the Agfa Thermolite processless plate. No processing device, and no development chemistry are needed. A wash-off step is required after imaging, which is carried out on press during roll-up. 

The uniqueness of LiteSpeed technology is that the coating liquid is aqueous, it can be imaged with standard 830 nm thermal imaging technology; it is a non ablative technology, so no vacuum or other cleaning provisions are required for debris removal; and it offers the press latitude of a conventional printing plate, because it prints from a highly hydrophilic substrate. For more details read the publication in in the link in which it appeared : :-http://www.imaging.org/IST/store/epub.cfm?abstrid=4687  (The article is based on inputs from the abstract in the same site and more information is not available).

One more development that I read  was that of  KODAK SONORA XP Process FreePlates which according to the Manufacturers work without chemicals and water during processing of plates. This is simply processed in a box like processor which creates image on the ready sensitive plates that reduce costs, reduce environmental impact, offer better process control with  no conventional processing equipment or chemistry to deal with, etc.  SONORA Plates can be mounted on the machines and  printed like any other plate. This also free up space by eliminating processing equipment. Newspaper printers can get to press quickly by eliminating the processing step, along with its costs and variability, without sacrificing imaging speeds, automation, quality, and run lengths. 

SONORA XP Plates can be imaged on KODAK TRENDSETTER, KODAK MAGNUS, or KODAK ACHIEVE  Platesetters, and are qualified for many other thermal platesetters as well. SONORA NEWS Plates can be imaged on KODAK GENERATION NEWS or KODAK TRENDSETTER NEWS Plate setters.

Kodak claims that the Sonara XP plates are capable of running on sheet fed, heat set web, and commercial cold set presses. They can run applications such as commercial print, newspapers, offset packaging, and even short-run UV. They work with integrated and non-integrated, continuous and conventional dampening systems, and they use your current inks and fountain solutions. ( Ref: Kodak.com)

Read more on this in the White paper published from Kodak by clicking the following.

Friday, June 20, 2014

Random Thoughts - 3


In order to reduce the waste percentage of the printed stocks it is necessary that simplified system is worked out to enable better feed backs between the presses and the paper mill to sort out the technical problems arising out of Paper during printing.

It was often noticed that in a press where continuous printing is going on round the year, especially like Currencies, Stamps and Bank Notes to which specially manufactured paper is supplied, the paper has been found to be the cause of higher rejection. The details of the paper that caused the technical problem could not be identified by the printers quickly so that the corrective action can be initiated in the Paper mills. This is a major problem faced by those establishments that print the said documents continuously round the clock with huge stocks of paper stacked in their stores.

Even though the practice of first cum first served policy in issuance of Paper to the first printing area is enforced, in the subsequent printing processes you cannot expect the printer to ensure the use of same sequence of paper lots due to several technical issues such as drying of ink, paper stretch etc. Besides the said issues, the Printed lots generally gets mixed up in print storage in each of the print departments however carefully one may have stored them as the storage area is often a limited one.

During printing when certain defects are observed, it is customary to conduct a ritual like seeking information from the issuing department on the details of the paper issued. They will then go through the records to find out details such as the dates of receipt of such lots at stores, the dispatch dates from the supplier etc, etc which consumes time and human energy. Since the printed lots gets mixed up the details so collected may also be messy.

And again the dispute between the supplier and the customer persists. The customer may say that the problems pertained to a particular lot of paper and the supplier may seek more and more details like date of receipt, temperature, seasoning time, arrival of the shipment, and other receipt details which cannot be easily identified and given. The dispute generally linger on, and by the time an agreement is reached with regard to the details of the defective lots, usual apologies follow with the assurance to supply better paper in future. One fails to take note of the fact that by the time an assurance is obtained few thousand more tons of paper would have been manufactured and kept. This is an endless process. Therefore in order to work out some simplified system to give quick and correct feedback on the paper lot that caused the problem an imprint can be printed in the paper making stage. Such an exercise can certainly reduce human energy in tracking and tracing and ensure faster communications with fool proof details to take corrective actions in few hours.


METHODOLOGY

1. Whenever the Paper is manufactured, an imprint can appear beyond the print edges but inside the cutting edges of the paper in the web in such a manner and position that the imprint will still appear after the Web paper is trimmed to size and meant for printing machines. The imprint can be done using a Ink Jet printer.

2. For example the imprint can begin with date something like 01.01.2014 etc which should be changed by the supervisor at the beginning of each day from a central command or it can be fitted with auto change date system.

3. Date to be followed by the shift prefix say “I” for the first shift, “II ” for the second shift and “III” for the third shift and so on.

4. If the sheet row in the web is first the code could be F, and for the second it could be S and so on. For the machine detail indicate A, B and so on (See the illustration to understand the sheet row).

5. The serial no of sheets can then begin say starting from 00000001 for the first row. Again 00000001 for second row also as the sheet position will come as prefix or anything like it.

6. Next day again with the change in the date the sheet will have the first serial no for the day like 00000001 for the first row. Again same no 00000001 for second row .

7. I guess that the consumption of ink will be very minimal. In fact it will not be even 1/1000th of the cost of paper per MT.

8. In fact if the auto dates and time changer is provided with the Ink Jet printer, it will automatically record the time of manufacture. The auto time changer can be adjusted in such a manner that the time of manufacture will change every one hour in the following manner:

12-05-2014 : 10.30
12-05-2014 : 11.30
12-05-2014 : 12.30
12-05-2014 : 13.30
and so on

9. For example the paper lots produced on 1st January 2014 in the first shifts will have the following imprints.

01012014 I A F 00000001
01012014 I B S 00000001
01012014 I C T 00000001


a) '01012014' represents the date, month and year i.e 01-01-2014
b) 'I' represents the shift i.e first shift
c) 'A' or 'B' or 'C' represents the machine No
d) 'F' or 'S' or 'T' represents the first, second or third rows of paper in the web

e) 00000001 is the serial no which will change as 00000002, 00000003 and so on till the end of the shift .

10. For the second day the imprints will appear as
02012014 I A F 00000001
02012014 I B S 00000001
02012014 I C T 00000001 
and so on as above


11. The fitment will also be simple and not complicated as the jets are to be connected to a rod over web in between the drying unit and the winding unit.

          



What are the advantages ?
1. While the paper is manufactured the paper edges are also watermarked as Front, Middle or the Back edge of the paper . This can be dispensed with.

2. The ream label contains the name of the operator, the date of printing, the shift, personnel who handled it etc. This can be discarded by pasting only the firm's label .

3. In the event the presses face problem in a particular lot, they can easily identify the correct sheet details and communicate to the manufacturer for taking corrective action.

4. Once the details are received from the customer the manufacturer can immediately identify the problems or identify the erring crew for the lapses without wasting time.

5. It will be easier to track the faults in minutes with the details received. The complainant will also find it easier to send the correct information pertaining to the defective lots.