From presses to printers
Gutenberg’s printing press of the 1440s could print a few hundred pages a day. Today’s printing machines can print tens of thousands of newspapers an hour, and a printer on your desk can print photos, documents and even solid objects. This lesson explores how printing machines evolved after Gutenberg.
Key developments
| Year | Invention | Impact |
|---|---|---|
| 1440s | Gutenberg’s movable-type press | Books became widely available in Europe |
| 1800 | Iron hand press (Stanhope) | Stronger, larger pages |
| 1814 | Steam-powered cylinder press (Friedrich Koenig) used by The Times in London | About 1100 sheets per hour |
| 1843–1847 | Rotary press (Richard Hoe) | Type on a rotating cylinder; millions of copies per day for newspapers |
| 1886 | Linotype machine (Ottmar Mergenthaler) | Typed whole lines of metal type, replacing hand-setting |
| 1904 | Offset printing (Ira Washington Rubel) | Fast, high-quality printing; still used for most books and magazines |
| 1938 | Xerography, the first photocopying process (Chester Carlson) | Led to photocopiers |
| 1969–1971 | Laser printer (Gary Starkweather at Xerox) | Fast, sharp office printing |
| 1970s–1980s | Inkjet printer | Affordable home printing |
| 1980s | 3D printer (Chuck Hull, stereolithography, 1984) | Printing solid objects |
How different printers work
Offset printing
- An image is put onto a metal plate.
- The plate is treated so ink sticks only to the image areas and water sticks to the blank areas (oil and water don’t mix).
- The plate transfers ("offsets") the ink onto a rubber blanket cylinder.
- The blanket presses the ink onto paper.
The soft rubber blanket helps print sharp images on many surfaces. Huge offset presses fed by giant rolls of paper print newspapers, books, magazines and packaging.
Inkjet printers
An inkjet printer sprays tiny droplets of ink, each smaller than the width of a hair, through microscopic nozzles. A print head moves back and forth across the paper.
| Type | How droplets are made |
|---|---|
| Thermal inkjet | A tiny heater boils ink, forming a bubble that pushes out a droplet |
| Piezoelectric inkjet | A crystal flexes when electricity is applied, squeezing out a droplet |
Laser printers
A laser printer uses static electricity.
- A drum is given an electric charge.
- A laser "draws" the image by changing the charge on parts of the drum.
- Powdered ink called toner sticks to the charged areas.
- The toner is transferred to paper.
- A heated roller (the fuser) melts the toner onto the paper. That’s why pages come out warm.
Laser printers are fast and good for printing lots of text.
Printing in colour
Colour printers use four inks: CMYK.
| Letter | Colour |
|---|---|
| C | Cyan |
| M | Magenta |
| Y | Yellow |
| K | Key (black) |
Printers combine tiny dots of these colours to make every other colour. Look closely at a printed magazine photo with a magnifying glass and you’ll see the dots.
Screens use RGB (red, green, blue light), while printers use CMYK (inks that absorb light). That’s why colours sometimes look different on screen and on paper.
3D printing
A 3D printer builds solid objects layer by layer from a digital design.
| Method | How it works |
|---|---|
| Fused filament (most common) | Melts plastic filament and lays it down in thin layers |
| Stereolithography (SLA) | A laser hardens liquid resin layer by layer |
| Metal printing | Lasers fuse metal powder |
3D printers make prototypes, replacement parts, prosthetic hands, dental crowns, models and even houses. Some researchers are working on printing living tissues.
Printing in Canada
- The first printing press in what is now Canada was set up in Halifax in 1751.
- Canada has a large pulp and paper industry that supplies printing paper.
- Modern Canadian printers produce books, newspapers, packaging and labels.
Printing and the environment
| Issue | Solution |
|---|---|
| Paper use | Print double-sided; print only what you need; use recycled paper |
| Ink and toner cartridges | Recycle them |
| Energy | Turn printers off when not in use |
| E-waste | Recycle old printers |
Common mistakes
- Thinking printing stopped changing after Gutenberg.
- Thinking printers mix inks before printing. They place tiny dots of each colour side by side or on top of each other.
- Thinking 3D printing is only for plastic. It also uses metal, concrete, resin and more.
Try it yourself
- Look at a newspaper photo and a printed photo with a magnifying glass. Can you see the coloured dots?
- Make a mini offset print: draw with a crayon on paper, paint over it with watery paint, and press another sheet on top.
- Design a simple object that could be 3D printed. Sketch it from three angles.
Quick recap
- Printing machines evolved from Gutenberg’s press to rotary, offset, laser, inkjet and 3D printers.
- Offset printing transfers ink from a plate to a rubber blanket to paper.
- Inkjet printers spray tiny ink droplets; laser printers use static electricity and toner.
- Colour printing uses cyan, magenta, yellow and black dots.
- 3D printers build objects layer by layer.