Modern offset printing is known for its high quality and consistency. The precision with which the ink is applied to the medium is superior to those of popular ink jet or laser printers. Offset print jobs do require more work to set up; but for a moderate to large production run, they can be even less expensive than digital printing.
Commercial Offset Printer – Austin MMP
If you need large quantities of top quality printed posters, flyers, leaflets or catalogs, offset printing is usually the best solution. Modern high tech computerized press control and offset publishing systems enable Austin MMP to set up and execute high volume print jobs at a remarkably low cost.
Our high tech Digital Imaging (DI) presses can print any CYMK or Pantone colors you choose. In contrast with conventional digital printers, the DI offset publishing process gives superior color consistency and edge definition. The state-of-the-art DI press in our fully-equipped Austin print shop can produce top quality images and text on thick paper (up to 130#) or card stock.
For high quality cost-effective print services – call AustinMMP (512) 454-3838
What is Offset Printing?
Offset lithography is the most popular method for high quality high volume commercial publishing. The process begins by creating images on metal plates, which are then transferred to rubber rollers or sheets, and then to the print medium – typically paper or card stock. This two-step methodology eliminates direct contact between the plates and print media, reducing wear on the plates. The flexibility of the ‘intermediary offset’ or ‘blanket’ rubber sheet/roller enables it to faithfully transfer the image to textured media like cloth, canvas, wood or other rough surfaces.
Commercial offset printing originated in 1875 with England’s Robert Barclay and the invention of the rotary lithographic press. There have been many technological improvements since then – primarily in the areas of automation, inks, speed and paper handling. In a modern DI press, the images and text are transferred directly to the printing plates. The inking system and dampening system place ink and water (in the non-printed area) on the plate, operating in sync with the blanket and impression cylinders. Computer control of these and the print medium enables the system to achieve high speed and excellent reproduction quality.
The main advantages of DI offset printing over digital or other technologies are:
- Consistently sharp images and text with uniform colors and precise edges
- Less costly than rotogravure or photogravure intaglio printing
- Precise color intensity adjustments via automated ink quantity control
- Low unit cost due to extended print plate life and less maintenance
- Digital control reduces plate production cost and set up time
Call MMP (512) 454-3838 today to discuss your printing requirements.
The Offset Publishing Process
Lithography and offset printing are based on the fact that oil and water resist mixing. The printing plate surface is coated with oily ink on the image portions, and an aqueous ‘fountain solution’ where there is no image. The repulsion of the oil and water is what gives the offset printed product its sharply defined image edges and crisp characters. The word ‘lithography’ is derived from the Greek words lithos (stone) and graph (writing). Originally lithograph presses used stone plates; now thin metal sheets (typically aluminum) are most common.
Offset inks are generally more viscous than with other print technologies. The thicker ink (sometimes called ‘paste ink’) adheres better to the print and offset cylinders – improving the quality and consistency of the finished product. The amount of research that has gone into creating ink with the best combination of opacity, body, temperature and stability is truly remarkable.
From design to completed product, the offset publishing process has three phases:
Pre-Press and Testing
In digital pre-press, film negatives are created from the image digital files. Then the images from the negatives are transferred to four print plates – one for each color: C/M/Y/K. The plates are then installed on the four plate cylinders. After loading the inks and making any mechanical adjustments, a small test run is conducted to ensure that the images are accurate and properly aligned. The press operators also check to see if the ink is flowing properly and being delivered to the plate cylinder, offset cylinder and ultimately the target medium.
There are two types of media feeders for offset work – sheet feed and web feed. Sheet feeding entails an individual sheet for each finished unit, and is most commonly used for small production runs. Web feed employs large rolls of paper (many units per roll) and is the standard for large offset print runs. As the paper is fed into the press, it runs sequentially between each of the four colors’ impression and offset cylinders, transferring each color to the medium in turn.
Trimming, Finishing and Bindery
Once the finished product has left the press, it needs to be trimmed to size. Depending on the nature of the end product, it may require finishing – embossing, debossing, foil stamping or special coatings. Finally, the offset printed material may be folded (newspaper or ad circular), stapled (pamphlet or perfect binding) collated and/or bound to produce the final form of the product.
The precision, flexibility and economy of commercial offset printing are what make it the standard for large scale commercial publication work like metropolitan newspapers, magazines, books and direct marketing materials.
Call us to discuss your project requirements and what type of technology is best for you. We would love to make you our next happy customer.
MailMarketPrint (512) 454-3838 – Digital and Offset Printing – Austin TX