Material Properties – Paper & Boards

1. LESSON 3/5 Material Properties – Paper & Boards • Within this lesson you will cover: • Develop an understanding of the different printing methods which can be applied to both paper and boards (within school and industry). • Develop an awareness of their suitability for specific products and scales of production.

2. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards DO NOW ACTIVITY In a pairs, discuss the benefits of printing to: • The user • The client Be prepared to share with the class your discussion and answer. WHAT DO YOU THINK?

3. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRIOR KNOWLEDGE HANDS UP, DON’T SHOUT OUT! Can you name a printing processes that you already have knowledge off.

4. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Commercial printing processes are distinguished by the method of image transfer used. Depending upon the process, the printed image is transferred to the paper either directly or indirectly: • Direct printing: Image transferred directly from the plate cylinder to the paper e.g. flexography, screen printing and letterpress printing processes • Indirect/ offset printing: Image is first transferred from the plate cylinder then to the paper e.g. offset lithography , which is most widely used commercial printing process

5. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Screen Printing Screen printing is a widely used commercial printing process for producing many mass or large-batch produced graphics, such as posters or point-of-sale display stands. A stencil is used to block off areas of the screen with a non-permeable material. This stencil is a negative of the image to be printed so the open spaces are where the ink will appear. Screens and stencils are produced using photo-emulsion technique Screen print video: https://youtu.be/gNWS6DrDOEM

6. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Flexography Printing Flexography video: https://youtu.be/goavE0R-ySY Flexography is often used for printing on plastic, foil, film, cardboard or other materials used in the packaging industry. Printing machines using flexo technique are based on flexible plates made of photopolymer. Using laser or through UV exposure on to the plates, the film negative image that is required is then imprinted. A thin layer of ink is deposited on the cylinder. A spatula called Doctor blade cleans the excess ink from the anilox, leaving only the desired amount in anilox cells (fine dimples). Anilox rotates & comes in contact with the plate, receiving the amount of ink required to make the image transfer on the print media. Each print unit prints a single process of colour: C= cyan M= magenta Y=yellow K=black

7. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Offset Lithographic Printing Lithography works on the basis principle that oil & water don’t mix (repel each other). Modern high volume lithography is used to produce books, posters, newspapers, packaging & mass-produced items in one production run. With some modern lithography printing machines the image is put onto the printing plate by shining UV light through a negative (similar to a photograph negative). The plate is coated with a chemical which allows the ink (made from oil) to attach to the image area. Lithography machines can print on both sides of paper/card & they rely on four basic colours – CYMK Lithography video: https://youtu.be/5LMU-zB8Sro

8. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Digital Printing Modern printing methods such as laser & ink-jet printing are known as digital printing. In digital printing, an image is sent directly to the printer using digital files. This eliminates the need for a printing plate, such as offset printing, which can save money & time. Unlike offset printing, you don't have to deal with colour separations and plate-making when doing digital printing. However, things like colour calibration and using printed colour guides can be important for obtaining the kind of results you want from colour digital printing.  Digital printing video: https://youtu.be/J_zv5V2hCzs Digital printing/ toner video:https://youtu.be/WB0HnXcW8qQ

9. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES Advantages, disadvantages & Applications Using the knowledge you have learnt during todays lesson complete the table worksheet.

10. Paper & Board Printing Processes. Advantages, disadvantages & Applications

11. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards PRINTING PROCESSES

12. Objective - Learner will gain knowledge and understanding of different printing methods which can be applied to both paper & boards HOMEWORK • A two colour design will be added to a concert ticket using screen printing process. Explain two reasons why screen printing is a suitable method for batch production (4marks) • The graphics on some cans are applied using flexography printing process. Using annotated sketches, describe the flexography process. (5marks) • Figure 1 shows a diagram of the offset lithographic printing process. Figure 1 • (i) Complete the diagram by labelling each of the indicated parts of the offset lithographic printing process. (5marks) (ii) On the diagram indicate the direction of rotation of cylinder X. (1mark)

13. A two colour design will be added to a concert ticket using screen printing process. Explain two reasons why screen printing is a suitable method for batch production (4marks) • The graphics on some cans are applied using flexography printing process. Using annotated sketches, describe the flexography process. (5marks) • Figure 1 shows a diagram of the offset lithographic printing process. Figure 1 • (i) Complete the diagram by labelling each of the indicated parts of the offset lithographic printing process. (5marks) (ii) On the diagram indicate the direction of rotation of cylinder X. (1mark)