Category: Printing press problems

Printing press problems

The printing press is a device that allows for the mass production of uniform printed matter, mainly text in the form of books, pamphlets and newspapers.

Created in China, the printing press revolutionized society there before being further developed in Europe in the 15th Century by Johannes Gutenberg and his invention of the Gutenberg press. No one knows when the first printing press was invented or who invented it, but the oldest known printed text originated in China during the first millennium A.

The Diamond Sutra was created with a method known as block printing, which utilized panels of hand-carved wood blocks in reverse. Some other texts have survived from Dunhuang as well, including a printed calendar from around A. It was during this period of early printing that rolled-up scrolls began to be replaced by book-formatted texts. Woodblock printing was also used in Japan and Korea at the time, and metal block printing was also developed at some point during that period, typically for Buddhist and Taoist texts.

Moveable type, which replaced panels of printing blocks with moveable individual letters that could be reused, was developed by Bi Sheng, from Yingshan, Hubei, China, who lived roughly from to A. The first moveable type was carved into clay and baked into hard blocks that were then arranged onto an iron frame that was pressed against an iron plate.

Shen Kuo explained that Bi Sheng did not use wood because the texture is inconsistent and absorbs moisture too easily, and also presents a problem of sticking in the ink. The baked clay cleaned-up better for reuse. By the time of the Southern Song Dynasty, which ruled from to A. Massive printed book collections also became a status symbol for the wealthy class. Woodtype made a comeback in when Ching-te magistrate Wang Chen printed a treatise on agriculture and farming practices called Nung Shu.

Wang Chen devised a process to make the wood more durable and precise. He then created a revolving table for typesetters to organize with more efficiency, which led to greater speed in printing. It was exported to Europe and, coincidentally, documented many Chinese inventions that have been traditionally attributed to Europeans. Goldsmith and inventor Johannes Gutenberg was a political exile from Mainz, Germany when he began experimenting with printing in Strasbourg, France in He returned to Mainz several years later and byhad a printing machine perfected and ready to use commercially: The Gutenberg press.

In order to make the type available in large quantities and to different stages of printing, Gutenberg applied the concept of replica casting, which saw letters created in reverse in brass and then replicas made from these molds by pouring molten lead. Researchers have speculated that Gutenberg actually used a sand-casting system that uses carved sand to create the metal molds.Printing is a mature industry and most printers have learned to achieve quality results while keeping costs under control.

Sometimes however, the printed result may not match your expectations. This page describes common printing issues, what causes them and how they can be avoided.

Keep in mind that printing is a physical process: some of the effects that are described are down to physical limitations. Much like the presence of gravity, there are natural effects that simply have to be taken as they are.

What: Small non- or partially inked circles. The example below is taken from a magazine article. Why: Hickeys are caused by dirt, paper fibers or hardened specks of ink on the printing plate or blanket. The problem is most visible in areas of heavy ink coverage. How to avoid: If a publication contains large solids, it can be difficult for printers to avoid an occasional hickey, especially on fast presses running large jobs. How to avoid: This is a quality issue but you should keep in mind that the choice of paper stock also plays a role.

What: The content of the opposite side of a page is visible, as shown in the theater guide below where two pictures of the back of the page shine through. Why: This effect is caused by a combination of a specific paper stock and fairly heavy ink coverage on the other side. How to avoid: Selecting a heavier paper stock helps. A designer can minimize this effect by properly aligning the content text columns, image placement, folio.

printing press problems

Object moire is a pattern that is visible in an image or artwork. The example below shows an picture taken in a museum. The pattern in the fabric behind the statue clashed with the CCD-pattern of my D70 digital camera, causing a weird color pattern to appear. It occurs when the optical system of a scanner interferes with a pattern in the orginal that gets scanned.

This easily happens if you try to scan a printed original but it can also occur with pictures that have a repeating pattern in them such as a brick wall or textiles. If the screening interferes with patters in the supplies images, the printer could have avoided this unless.Reference Guide. Print Quality Problems Horizontal banding Vertical misalignment or banding Incorrect or missing colors Blurry or smeared printout Printer rollers leave unwanted marks on your documents Print quality does not improve after head cleaning If you are having print quality problems, first perform a test print.

Then, compare your test printing with the illustrations below. Click the caption under the illustration that best resembles your printout.

printing press problems

Printer rollers leave unwanted marks on your documents. Horizontal banding Try one or more of these solutions:. Make sure that the printable side of the paper is face up in the sheet feeder.

Run the Head Cleaning utility to clear any clogged ink nozzles. Run the Print Head Alignment utility. Clear all customized settings by selecting Automatic as the Mode setting on your printer software's Main menu Windows or in the Print dialog box Macintosh. If the light is flashing, replace the appropriate ink cartridge.

See Replacing an Empty Ink Cartridge for details. Make sure that Maximum is not selected as the Printable Area setting in your printer software. When this setting is selected, banding may occur in the expanded area. Make sure that the Media Type selected in the printer software is appropriate for the type of media loaded in the printer.

Make sure the MicroWeave check box is selected when available in the Advanced dialog box. For Windows users, see Making Advanced settings for details. For Macintosh users, see Making Advanced settings. Vertical misalignment or banding Try one or more of these solutions:. Clear the High Speed check box in the Advanced dialog box. Make sure that the Media Type setting selected in the printer software is appropriate for the type of media loaded in the printer.

How to Solve Common Printing Problems

Incorrect or missing colors Try one or more of these solutions:.Post a Comment. Tuesday, August 16, Misregistration on press. You may have the most accurate CtP, the best and newest offset press, however, you are still covering absorbent paper with ink and water and squeezing under pressure in the press.

The result is that there will always be a chance of misregistration in the presswork. Here are a few of the most commonly encountered types of misregistration: Back sheet flare a. As the sheet is pulled through the press the tail corners of the sheet fan out slightly causing misregister in the corners.

printing press problems

Back stretch Back stretch can occur if blanket and packing on one or more units may have been compressed during the pressrun, causing change in the print length. Web growth One type of web growth occurs on web press as the paper streams from ink unit to ink unit. The paper edge gives up moisture at a different rate than the middle of the web. This changes the size of the paper and hence causes misregistration. Fit Misregistration occurs when one or more colors do not fit with the others in a set.

It is typically caused by the film, or plate in a CtP device, changing size due to environmental temperature changes. Despite the fact that some degree of misregistration is normal in the printing process, and that it impacts the integrity of the final presswork - as far as I can determine - it's surprising there are no official specifications for what is an acceptable tolerance for misregistration. In multicolor printing, when all the layers of inks are in perfect register, one is not aware of the individual ink layers, only the image created by their combination.

However, if one or more of the individual ink layers begins to move out of register, the image begins to appear softer, with lower detail definition. Color and tone may subtly shift. And if the ink layers continue to move further out of register, color fringes begin to appear at the edges of detail, and finally the color image breaks up. There is no absolute point at which the loss of register between the ink layers causes the color or image integrity to become unacceptable.

And while misregistration can be expressed in thousandths of an inch or millimeters or in angular degrees, its effect on color register will change depending on several factors. For example, misregistration is most visible in reverse type within a four-color process area.

The sharp edges of the type and the high color contrast between the inks and the bare paper exaggerate the visibility of any color fringing caused by misregistration. But color images with little sharp detail or where a black border hides the edges can tolerate a greater degree of misregistration before the reproduction is seen as unacceptable.

Experienced press operators have an intuitive understanding of these factors which has led - in the absence of industry specifications - to a pragmatic approach to the problem of misregistration. That is enough to shift a rosette from clear-centered to dot-centered.

So, for example, at lpi that's about 0. In register - clear-centered rosettes with a uniform edge. Out of register by a distance of one half a row of dots - clear-centered become dot-centered rosettes with, in this case, one color layer hanging outside the other three creating a color fringe.

Printing press

How the press operator measures misregister Of course, press operators cannot directly measure the amount of misregistration. Instead, when they look closely at the press work through a loupe they employ a simple visual trick: The press operator visualizes the width of a row of halftone dots divided into quarter distances. The solid black lines show the width of one row of halftone dots.

The long-dashed black line goes through the center of the dots. The short-dashed lines divide the width of the dot row into quarters. For a lpi halftone, the spacing between adjacent dotted lines is 0. Although trade practice has been to hold misregistration to within one half row of dots - which seems to be a very tight tolerance - there is still a negative impact on the integrity of the press work.

As the dot structure goes from clear-centered to dot-centered as it drifts out of register, the rosette becomes twice as visible effectively halving the screen ruling. So, a dot-centered lpi rosette structure is as visible as a coarse 75 lpi screen. This is often seen like a rash on important skin colors where small amounts of misregistration make the rosette appear then disappear. Lastly, misregistration changes the overprint ratios of wet and dry trap - causing a color shift.Why don't fictional characters say "goodbye" when they hang up a phone?

If we can't tunnel through the Earth, how do we know what's at its center?

Quality issues in print

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Wiki User The printing press caused the ability to produce counterfeit money easier. The introduction of counterfeit money threatened to devalue currency. Asked in Typewriters Typewriter or printing press? Printing Press came out first. Asked in Inventions Why was the printing press a step forward for printing?

Printing press plays a major role in meeting the printing needs of industrial sector. If the printing press was not introduced the industrial needs could not be satisfied. The printing press have brought a revolution in the printing industry. The books, magazines, news papers and office stationary on large scale is just due to printing press. Asked in Example Sentences Can you start a sentence with the word gravure printing? Gravure printing requires a printing press.

Asked in Inventions Invented the printing press? The printing press was invented by a man named Johannes Gutenberg. The printing press was invented in the year of Asked in Inventions, History of Europe Who invented the printing press?

Printing Press was invented by Johann Gutenberg. Asked in Inventions When did the Printing Press?Johannes Gutenberg's invention of the printing press in opened lines of communication throughout the world. The advent of the printing press changed the face of journalism and education. However, pollution issues surrounding modern industrial printing and paper manufacturing have developed since Gutenberg's revelatory invention. The culmination of toxic ink and bleaches used by some modern manufacturers can have adverse effects on the surrounding environment.

The first mechanical printing press was a culmination of ideas: the manufacturing of paper from rags, metal type and oil-based ink. Developments in printing began in Europe some time during the late s and early s. Trade among European capitals and Asia introduced inventors in Europe to new method of paper manufacturing using discarded rags, a much cheaper process than the calfskin formerly used in the West.

The first printed and bound books were concerned with religious topics. They were large, expensive and heavy.

These were mostly used in religious ceremonies and as family heirlooms. Aldus Manutius, a Venetian printer, printed the first small, portable books in The accessibility and portability of the pocket books helped the spread of literacy. The printing of affordable books brought in a great profit and soon inspired printers to continue the pocket book practice with secular books.

This influx in the amount to printed material eventually led to a great growth in literacy. It also exposed the public to printed material not censored by the church. These was a cause for concern among church leadership, as the scientific findings being circulated threatened some the popular religious views. This conflict between religion and the printing press came to a climax with a monk named Martin Luther in ; he was able to spread his discontent with the established church through the printed word.

Inks used in industrial printing effect the environment in various ways. Vent fumes are fumes released by the inks into the atmosphere during printing. These fumes can be harmful when inhaled. Other inks create problems after they are discarded. The U. Occupational Safety and Health Administration provides guidelines for worker safety in the print industry, such as wearing protective gloves and masks when handling potentially harmful chemicals.

Environmental regulation falls to the U. Environmental Protection Agency, which sets pollution level standards for the chemicals used to print. The chemicals required to break down the ingredients for paper production emit fumes. These fumes are toxic to workers in paper factories. According to a study published in "Allergy," some of these chemicals have caused chronic respiratory allergy symptoms that can lead to more severe respiratory issues later in life.

Tiffany Ross is a writer and actress who has been working in Chicago since Ross is a world traveler with experience working overseas. Share It. About the Author.Extend the ink with transparent white. The same concept can be used if you have a heavy image on the plate where it pulls too much ink out of the head faster than it can be delivered but need the color to be light. Ink roller mark in paper This makes troubleshooting offset printing ink a daunting task at times.

There are so many demands on ink to print good quality in a complicated process. Let's examine how you can troubleshoot just a few problems with your offset printing ink. High Dot Gain Ink is not the only factor to consider in this case.

Printing Press

There are many other factors to consider relating to your plates, pressure settings and chemistry. Let's just consider a couple possibilities that may involve the ink itself that is causing high dot gain. Increasing your viscosity may make an improvement, but cause problems in other areas. Ask your supplier for help to understand all the underlying issues.

Cause: Improper ink and water balance. It may be that you are not able to be within a proper ink and water balance window due to the inks properties.

Ask your ink manufacturer for a certificate of analysis and pay attention to values that indicate such things as water pickup. Piling Again, let's just look at the factors relating to ink. Piling occurs on all offset printing presses, but can be controlled. A good quality offset printing ink will cause minimal piling. Here are some possibilities that can cause piling that relate to ink. Anti piling agents are added to fountain solution to control it.

You may consider running your water just above minimum and see how the ink reacts. Consider too that often paper is the culprit, so you must examine the piling itself to be certain where it's coming from. As well, consult your offset printing ink manufacturer to discuss the quality of the ink. Setoff When troubleshooting setoff problems, understanding the problem requires a thorough understanding of the drying process. With heatset printingthe flash point of the ink will have a large bearing on whether it dries properly.


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