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'

Sunday, September 23, 2012

Alphabet- M




1. Make ready: All the activities like setting the machine feeder, positioning the plates/ blocks with text matter, readying blankets (in offset and Intaglio), inking, loading the paper, registering the images on paper, setting appropriate colours etc which are required to be carried out before commencing the actual run on the machine or any such productive machinery activity that stretches to Numbering, mass stock trimming etc are called make ready. Once the make ready is over the machine gets ready for final run. This also applies to the respective activities in bindery dept where all the material required are pooled and kept ready for final operation. The paper used for make ready is treated as waste paper, but used for trial sheets till they become non usable. Getting everything right during make-ready helps to ensure a quality print run.
2. Machine Glazed (MG) Paper: Paper having high-gloss finish on one side is called Machine glazed.  This is done  in the paper mill by passing the finished paper in a Yankee machine which has a single highly-polished steam-heated drying cylinder.  The classic example of machine glazed paper is the tissue papers used in the parties, functions and restaurants to wipe hands , for printing posters,  general wrapping, scrunching, void-filling and for interleaving etc. It is also extensively used by the garment, bakery, removal and retail trades. There are two varieties of tissue papers available.  One is white in colour and the other is machine glazed Kraft paper. In the issue of tissue paper should not be confused with standard MG (Machine Glazed) acid free tissue or the more luxurious, premium MF (Machine Finished) acid free tissue used for face cleaning. 

3. Male Die: Pl read details under Die and Debossing. The die that applies force while debossing is called male die.
4. Manuscript : Any original material – either hand written, typed or submitted as soft copies for printing is called the manuscript. The manuscript is supplied by the author who penned the theme or submitted by the publisher to the printer.
5. Margin : The un printed areas or white space given around the four sides of the printed material is called margin. The margins depend upon the lay out prepared. 
6. Mask or masking : The process of blocking out the unwanted, not to be printed  portions in the negatives  or positives from getting  exposed on to the plates during plate-making is called masking. It is done by blocking such areas using black paper, or painting with special opaque colour (reddish in colour). This is also called retouching work in the process department. 
The following illustration will explain this type of masking.

Similarly, by a process called Photographic masking technique , the colour separated negatives or positives are color corrected to bring the negative or positives close to produce images matching the original colors. During color separation if some color separated negatives or positives registered undesirable colour in one particular film , they have to be removed failing which the reproduced print will not match the original colours as seen in the image.
In such cases the artists used to retouch the negatives or positives using certain chemicals to either add or remove those un desirable or strengthen deficient portions before processing the plates for printing. This is called dot etching.
For example in the color separated negative/positive meant for printing yellow color, due to process deficiency or technical fault some of the cyan portions of the images in some areas have also been recorded though as weak image. If the uncorrected yellow negative or positive with the said defect is printed, the yellow areas will appear bluish yellow when the Cyan is over printed . The yellow which should stand out in true colour will appear slightly bluish yellow due to the presence of too much Cyan in those areas .
All such defects when can not be corrected manually by the artist especially in high quality close works, the undesirable portions need to be corrected by photographic means using certain additional filters or color correction masks and three pin register systems supplied by the Photographic firms. Such an exercise is also called photographic Masking technique .  
In color separations, an intermediate lithographic negative or positive used in color correction and employed during the direct screening method. For use in making color corrections, a mask made from rubylith or film is used to alter precise areas of tone or color on litho dupe film. Now a days even the photographic technique of masking is slowly vanishing due to scanners and auto colour correction process equipments .
The following illustration will explain photographic type of masking. 

  
7. Mid tones : In any of the photographs or illustration, the tones (shades) represented  by dots ranging from 30 to 70 percent of coverage are called middle tones (mid tones).
8. Misting : Ink Misting is a printing ink defect in which ink flies like mist and prints a faint image. This is common defect that occurs particularly in Offset printing presses that run at high speeds. This is a phenomenon of droplets of ink being thrown off the roller chain during machine run. This is also referred to as flying of ink. The possible causes for this defect is too heavy an ink film being run on the rollers, press speed is excessive for the type of work being printed, improper ink- water balance in Offset printing machine, rollers worn out,  incorrectly set rollers, the ink  emulsification, too low  tack of the ink etc and during low humidity the static electricity on rollers induces misting .
9. Moire effect : Undesirable pattern showing in the multi colored print due to improper use of halftone screens during processing the films. If the screen angle has not been properly set – normally for each color separation the screen angle is rotated by 15° - during halftone processing, the dots will not fall correctly and cause distorted un sharp image.
............Additions to alphabet M to be continued under M/2

1 comment:

  1. I really appreciate the idea behind this great post.You are doing a fine job.Keep it up.
    Farbkorrekturmasken

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