OFFSET WORKS
Offset printing is a widely used commercial printing method where the inked image is transferred (or “offset”) from a metal plate to a rubber blanket and then onto the printing surface (usually paper). 🖨️
How Offset Printing Works
- Plate preparation
The image or text is transferred onto a thin metal plate (usually aluminum). - Ink and water separation
The plate is treated so that:- Image areas attract ink
- Non-image areas attract water
This works because of the principle that oil and water do not mix.
- Transfer to rubber blanket
The inked image on the plate first transfers to a rubber blanket cylinder. - Printing on paper
The rubber blanket presses the image onto the paper or other material.
Basic Printing Flow
Plate → Rubber Blanket → Paper
Main Parts of an Offset Printing Machine
- Plate cylinder
- Blanket cylinder
- Impression cylinder
- Ink rollers
- Dampening system (water rollers)
Types of Offset Printing
- Sheet-fed offset – prints on individual sheets of paper
- Web offset – prints on large rolls of paper (used for newspapers, magazines)
Advantages
✅ High image quality
✅ Cost-effective for large quantities
✅ Consistent color printing
✅ Works on many paper types
Common Products Printed with Offset
- Books 📚
- Newspapers 📰
- Magazines
- Packaging boxes
- Posters
- Brochures