All about printing papers ..... 1

All about printing
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Written by: N.R. Jayaraman  
During the process of printing technical problems like void on print, fluffing, set off and elongation leading to mis-register etc surfaces and haunt the printers. While the voids on print and fluffing is because of the foreign particles and impurities embedded over the surface of the paper, the mis register mostly due to elongation and shrinkage of the paper is due to the surface behaviour of the paper used. The reasons for the problems are many which may be due to the changes made in the processing techniques, quality of the raw materials and chemicals used during paper manufacturing process etc. Unless some kind of standardization in the process of manufacturing paper in the mill and use of standard raw materials are established, such problems on the paper supplied by the paper mills would continue to occur.

Each printing process and kind of document required to be reproduced may require specific quality of paper and there cannot be common paper to meet the needs of all kinds of reproductions unless they are routine jobs like ledgers, bill books, notices, statements, simple magazines without high quality photo pictures, and other such documents used on day to day purposes which can be reproduced on any type of paper in simple processes of printing. In respect of quality jobs, each varying in nature, the wrong selection of paper not matching to the process and inks used  can contribute to production related technical problems.

Overtly the print medium, i.e. paper may appear to be a simple sheet of paper but many technical parameters to be maintained during manufacture may influence their ultimate the quality in meeting the job requirement and process and therefore except routine job printers, the specialist printers who use quite a huge quantity of specific paper suitable for specified reproduction usually procure made to order paper directly from the mills. In such an event they ensure that prior to supply, the specific quality parameters of the paper ordered by them are tested by their inspectors using different apparatus, instruments and equipments under standard conditions of testing as specified in TAPPI, ISO or other standards of different countries for those paper lots ready for dispatch. This is invariably practiced by the printers who use specific type of papers for specialized jobs on long term basis, especially like printing Bank note and Currencies, several type of Governmental documents like
Postal stationery including Stamps, Export- Import Licenses, Bonds, Several types of Labels embedded with security features for brand protection of products, Warranty, Guarantee of high value transactions and Educational institutional Certificates,  Legal documents and cartons. etc. There is vast variation in the basic qualities of paper used by commercial as well as security printers.
The testing of the paper is carried out under specified conditions  such as so and so RH and Temp in which the randomly picked up paper samples from the paper ready for dispatch will be kept conditioned for certain period of time  and then taken up for testing. Even small quantity of special effect paper procured by the security printers for specialized jobs for certain customers who insist on customized paper not supplied to others adhere to the principle of ordering paper inbuilt with pre testing conditions. 

If the paper related problems on the print is to be properly addressed, then the  expert printer need to have some knowledge on the basic structure and properties of such papers before procuring such paper to the process in which they are engaged.

In general, many varieties of papers are available in the market such as Bond paper, Writing paper, Tissue paper, Kraft paper, Printing paper, Cardboard, and Special effect papers with certain general features inbuilt in them. The special papers for Postal stationery including Stamps, Currencies, Licenses, Bonds, Brand protection labels, Warranty, Guarantee and Educational institutional certificates, Legal documents and Cartons are also manufactured by the mills but on  customized basis and supplied directly to the users under a contract. They are not supplied to other customers or sold in the market without consent from the original contractor. Each type of paper manufactured has  quality parameters such as Thickness, GSM, Moisture content, Bursting strength, Tensile strength, Porosity, Opacity, Tearing strength, hidden features like Shining fibbers, Elongation, Acid and Alkaline content limit etc, etc. Those parameters and their importance are explained separately. Each of those parameter vary on the paper manufactured depending upon their ultimate usage. 

The literacy rate and industrial development are both showing upward trend in demand for paper in India which is estimated to be over one hundred lakh metric tons plus to for various use including reading material and stationery besides paper meant for Currencies and bank notes. The paper importation for currencies alone is said to be 16 million metric tons per annum (Ref:

The consumption of paper and paper boards in India is estimated to be almost 100 lakh tons at present. Almost all types of paper mills in the country are increasing their production capacity and renovating their plants. As per the guesstimate of Indian Paper Industry circles by the end of 2025 the demand for paper in the country would be close to 2.5 crore metric tons.

The main source of raw material for manufacturing the paper is wood from trees. As the demand for more and more paper gained momentum all over the world, alternate use of raw material like Linen and Cotton rags began to be developed in place of wood since preservation of trees for ecological balance and environmental control measures became necessary and the search for further alternate sources began. The search culminated into the use of already used paper under the garb of recycling of paper.

Various types of papers 
Though many types of paper are manufactured, the basic process of manufacturing the paper remains the same except addition/ alteration in process flow, raw materials and chemicals used, which vary depending on their ultimate use.
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