Printing processes 2

The Printing ProcessBy: Joshua Davy 10D

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Screen printingTo Screen Paint:a The material being printed is place on top of the base. aThen the user would get out a template made of either rubber or card and then cut out the required shape out of its place, this template is then place on top of the paper.aA screen placed on top of the template, the screen is made out of Stretched nylon fabric in a wooden frame.aInk is applied on the nylon fabricaA blade is used to spread and push the ink in to the fabric through the template and on to the paper.aThe paper is taken out after this event and left to dry, the image of the template is left behind on the paper.

What is screen printing used for?aIt is used in every day packaging and T-shirts and posters.aAdvantages: screen printing is cheap, and it could be used on a large scale and many colors can be used during this process.aDisadvantages: The image is not as sharp as photocopying or printing. It also requires along time drying.

Gravure

To print using the gravure technique:s The cell are filled with liquid ink and a blade is pulled across the cylinder to remove and excess. s As the paper is fed through the press by a rubber covered cylinder, it is pressed in to the cells to pick up drops of ink from the final printed image.s The spirit –based ink dries through evaporation immediately after printing

What is gravure printing used for?sIt is used to print high quality art and photo graphic books, postage stamps, and expensive magazines.sAdvantage: consistent color, high speed, ink dries on evaporation, good results on cheap paper.sDisadvantage: High cost of printing plates and cylinders, only good for long print runs.

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PhotocopyingTo Photocopy:gThe first action you need to perform is to place an image face down on to the glass top, a light then scans the image and reflect the image from a white surface onto a charged rotation drum.gThe the drum loses its positive charge on the remaining lit up parts of the exterior. gThe toner is then attracted on to the positively charged parts of the paper while the drum is rotating.g The Drum rotates and the copier paper is move through the photocopier and the image gets transferred by the toner being applied to it

What Is Photocopying used for?gPhotocopying can be used for making posters on either large or small scale, or it is used to transfer designs onto transfer paper (this could be used for t-shirts or pencil cases)gAdvantages: Large amounts could be printed at one time.gDisadvantages: The image would not come out as clear as other images would using different types of printing.

Offset LithographyTo perform offset Lithography:x The aluminum printing plate has to have the image required so it stands out slightly. xThen the plate is dampened and then ink is applied on it.xThe water is then repelled from the damp surface.xThe inked image is then transferred from the plate cylinder to the blanket cylinder which prints onto the paper as it slips between the blanket and impression cylinders.

What is it used for?xLithography is used for menus, newspapers, high quality images, poster, and business cards.x Advantage: It is cheap to print, and it works on several different types of surfaces.x Disadvantage: The paper could stretch during the process, and the could might not be consistent.

FlexographyTo Print using the flexographic technique:mThe technique to flexography is remarkably similar to a letter press.m The image that is required stands in relief, the relief is made out of flexible plastic or a rubber printing platem The paint is the rolled on to the surface and the the paper is put on top of the printing plate.m The paper is pressed against the printing plate to ensure that the image is copied on the paper in full detail.

When Is Flexography used?mThis printing technique is normally used for newspaper, packaging, paper backs, and less expensive magazines.m Advantages: It prints at a high rate, it is easy to set up, it can be printed using letter presses as well.mDisadvantages: It is difficult to produce fine detail and the ink may not me consistent.