Difference between revisions of "AY Honors/Printing/Answer Key"

Revision as of 01:31, 18 October 2006

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1. Know how the following printing devices work:

a. Web press

b. Offset press

c. Photocopy machine

How a photocopier works (using xerography):

First, the surface of a cylindrical drum is given an electro-static charge by a high-voltage wire called a corona wire. The drum is coated with a photoconductive semiconductor material, such as selenium or germanium.
Then the light reflected from the scanned original document is beamed in a narrow band onto the surface of the drum. Only the white areas of the original document reflect light. The reflected light then hits the drum, which is specially conditioned to make it photoconductive. This means that wherever light hits it, the positive charges are conducted away to a ground.
As a result, the white areas of the picture are now neutral, and the black areas remain positively charged, yielding a latent electrical image on the surface of the drum.
The toner is negatively charged. Therefore, when it is applied to the drum to develop the image, it is attracted and sticks to the areas that are positively charged, just as paper sticks to a toy balloon with a static charge.
The toner image is then transferred from the drum onto a positively charged piece of paper.
The drum is then wiped clean and completely discharged by light, before beginning the process again.
The toner is a dry powder. If copies were to exit the photocopier covered in dry toner it would easily brush off. Toner usually contains a styrene or polyester resin, and with the application of high heat and pressure it melts and binds (or fuses) to the paper.

d. Letterpress

2. Know what the reference of pound means in determining the weight of paper. Know what the following paper types are used for:

a. Offset

b. Bond

c. Cover weight

d. Index

3. Tour a print shop or newspaper company. Write a 300-word report or give a three-minute oral report on the steps taken in the printing process that you observed.

4. Do some research to learn about the history of printing. Trace the development of printing by learning how printing presses have progressed to the present.

5. Know the different inks available for printing and their characteristics.

6. Know the meaning of the following terms:

a. Backing up: Printing things on the back side of a paper after the front side has already been printed.
b. Blanket: A thick rubber mat that transfers ink to the paper on a printing press.
c. Bleed: Print that goes all the way to the edge of a sheet as a result of trimming the paper.
d. Boldface
e. Camera ready art
f. Caption
g. Clip art
h. Collate: Sorting printed material in a precise order.
i. Color separations: To print color photos, the pictures must be divided into four colors - red, yellow, blue, and black. These four colors are then printed separately on the same page, with all the other colors being made by combining these four.
j. Contact print
k. Debossing
l. Embossing: Imprinting an image by pressing it into the paper forming a raised relief.
m. Engraving
n. Font
o. Ghosting: A faint copy of an image appearing on a page where it was unintended.
p. Intaglio: Intaglio (pronounced in-TAL-yo) is a printmaking technique in which the image is incised into a surface. Normally, copper or zinc plates are used as a surface, and the incisions are created by etching, engraving, or some other method. To print an intaglio plate, the surface is covered in ink, and then rubbed vigorously with a special cloth or with newsprint to remove the ink from the surface, leaving it only in the incisions. A damp piece of paper is placed on top, and the plate and paper are run through a printing press that, through pressure, transfers the ink from the recesses of the plate to the paper.
q. Jog
r. Matte: A dull, flat ink finish.
s. Negative: A reverse-color image. In a black and white negative, areas that are supposed to be white are black, and areas that are supposed to be black are white.
t. Paste-up
u. Register: To line up a piece of paper for printing so that the printed material is placed in the correct position on the page. This is important especially when printing separate colors in the 4-color process.
v. Set-off
w. Show through: When printing on one side of a page can be seen on the other side of the page.
x. Thermography: A photography technique in which the film captures the amount of heat emitted or reflected by an object instead of the amount of light reflected.
y. Water mark: A light design on a sheet of paper which can be easily seen if the sheet is held up to a light. U.S. currency has a lot of watermarking.
z. Work and turn: The process of printing one side of a paper and then flipping it left-to-right and printing the opposite side using the same guide rails.

7. Know the difference between half-tones, duo-tones, and the four-color process.

8. Interview a printer to find out the following:

a. What education is needed to get into the printing field?
b. What advancement opportunities are available in printing?
c. What does the future hold for the printing industry?
d. What do you do in your business to keep customers happy?
e. What career opportunities related to printing are available?

References

http://www.printusa.com/glos.htm Glossary of printing terms

@@ Line 4: / Line 4: @@
 ===b. Offset press===
 ===c. Photocopy machine===
+How a photocopier works (using xerography):
+#First, the surface of a cylindrical drum is given an electro-static charge by a high-voltage wire called a corona wire. The drum is coated with a photoconductive semiconductor material, such as selenium or germanium.
+#Then the light reflected from the scanned original document is beamed in a narrow band onto the surface of the drum. Only the white areas of the original document reflect light. The reflected light then hits the drum, which is specially conditioned to make it photoconductive. This means that wherever light hits it, the positive charges are conducted away to a ground.
+#As a result, the white areas of the picture are now neutral, and the black areas remain positively charged, yielding a latent electrical image on the surface of the drum.
+#The toner is negatively charged. Therefore, when it is applied to the drum to develop the image, it is attracted and sticks to the areas that are positively charged, just as paper sticks to a toy balloon with a static charge.
+#The toner image is then transferred from the drum onto a positively charged piece of paper.
+#The drum is then wiped clean and completely discharged by light, before beginning the process again.
+#The toner is a dry powder. If copies were to exit the photocopier covered in dry toner it would easily brush off. Toner usually contains a styrene or polyester resin, and with the application of high heat and pressure it melts and binds (or fuses) to the paper.
 ===d. Letterpress===
 ==2. Know what the reference of pound means in determining the weight of paper. Know what the following paper types are used for:==