Types of Commercial Offset Printing Part 1
There are several different forms of commercial offset printing. Each has a unique version of the original offset printing process, designed to meet the needs of specific printing requirements.
Offset duplicators are lithographic presses sized for one or two-color copies of 12” x 18” or smaller. The offset duplicators are for very fast printing, making up to 12,000 copies per hour. This process is often used for business cards, letter head, envelopes, and other simple print jobs.
With sheet-feed offset printing, pages are fed one at a time through the machine. The press uses mechanical registration to ensure equivalent printing from page to page.
The perfecting press is another name for the duplex press. This one is unique for its ability to print on both sides of the paper at the same time, an incredibly time-saving feature.
Web offset presses are designed for speed. With up to 3,000 feet per minute printed, the web offset printing benefits do not stop there. Some can even fold, cut, or perforate in process.
With heated web offset, high gloss pages, like those for magazines, can be printed with evaporation-setting inks that need heat to dry it onto the coated paper surface. Then, the paper passes through a “chill roll” to cool it down before any cutting or other processing can be done.
Coldset web offset is for printing projects that do not require the same high quality as a magazine. Newspapers are usually printed with a coldset web offset printing process. The ink simply dries as it absorbs into the newspaper it is printed on. But, as newspapers are competing in new markets, many are adding heatset towers to the line, or using UV inks that heatset or cure on the paper, rather than absorb, for a crisper, cleaner image and a more competitive look.