pinting machine

Screening

2008-12-17T00:08:00.001-08:00

Inks used in color printing presses are semi-transparent and can be printed on top of each other to produce different hues. For example, green results from printing yellow and cyan inks on top of each other. However, a printing press cannot vary the amount of ink applied except through "screening," a process that represents lighter shades as tiny dots, rather than solid areas, of ink. This is analogous to mixing white paint into a color to lighten it, except the white is the paper itself. In process color printing, the screened image, or halftone for each ink color is printed in succession. The screen grids are set at different angles, and the dots therefore create tiny rosettes, which, through a kind of optical illusion, appear to form a continuous-tone image. You can view the halftone screens that create printed images under magnification.

Traditionally, halftone screens were generated by inked lines on two sheets of glass that were cemented together at right angles. Each of the color separation films were then exposed through these screens. The resulting high-contrast image, once processed, had dots of varying diameter depending on the amount of exposure that area received, which was modulated by the grayscale separation film image.

The glass screens were made obsolete by high-contrast films where the halftone dots were exposed with the separation film. This in turn was replaced by a process where the halftones are electronically generated directly on the film with a laser. Most recently, computer to plate (CTP) technology has allowed printers to bypass the film portion of the process entirely. CTP images the dots directly on the printing plate with a laser, saving money, increasing quality (by reducing the repeated generations), reducing lead-times, and saving the environment from toxic film-processing chemicals.

Screens with a "frequency" of 60 to 120 lines per inch (lpi) reproduce color photographs in newspapers. The coarser the screen (lower frequency), the lower the quality of the printed image. Highly absorbent newsprint requires a lower screen frequency than less-absorbent coated paper stock used in magazines and books, where screen frequencies of 133 to 200 lpi and higher are used.

The measure of how much an ink dot spreads and becomes larger on paper is called dot gain. This phenomenon must be accounted for in photographic or digital preparation of screened images. Dot gain is higher on more absorbent, uncoated paper stock such as newsprint.

Color separation process

2008-12-17T00:07:00.001-08:00

The process of color separation starts by separating the original artwork into red, green, and blue components (for example by a digital scanner). Before digital imaging was developed, the traditional method of doing this was to photograph the image three times, using a filter for each color. However this is achieved, the desired result is three grayscale images, which represent the red, green, and blue (RGB) components of the original image:

The next step is to invert each of these separations. When a negative image of the red component is produced, the resulting image represents the magenta component of the image. Likewise, negatives are produced of the green and blue components to produce yellow and cyan separations, respectively. This is done because cyan, magenta, and yellow are subtractive primaries which each represent two of the three additive primaries (RGB) after one additive primary has been subtracted from white light.

Cyan, magenta, and yellow are the three main pigments used for color reproduction. When these three colors are combined in printing, the result should be a reasonable reproduction of the original, but in practice this is not the case. Due to limitations in the ink pigments, the darker colors are dirty and muddied. To resolve this, a black separation is also created, which improves the shadow and contrast of the image. Numerous techniques exist to derive this black separation from the original image; these include grey component replacement, under color removal, and under color addition. This printing technique is referred to as CMYK (the "K" being short for "key." In this case, the key color is black).

Today's digital printing methods do not have the restriction of a single color space that traditional CMYK processes do. Many presses can print from files that were ripped with images using either RGB or CMYK modes. The color reproduction abilities of a particular color space can vary; the process of obtaining accurate colors within a color model is called color matching.

Color printing

2008-12-17T00:06:00.000-08:00

Color printing is the reproduction of an image or text in color (as opposed to simpler black and white or monochrome printing).

While there are many techniques for reproducing images in color, specific graphic processes and industrial equipment are used for mass reproduction of color images on paper. In this sense, "color printing" involves reproduction techniques suited for printing presses capable of thousands or millions of impressions for publishing newspapers and magazines, brochures, cards, posters and similar mass-market items.

In this type of industrial or commercial printing, the technique used to print full-color images, such as color photographs, is referred to as four-color-process printing, because four inks are used: three primary colors plus black. The "subtractive" primary ink colors are cyan (a bright blue), magenta (a vivid red-purple), and yellow; which are abbreviated as CMYK.

Two graphic techniques are required to prepare images for four-color printing. In the "pre-press" stage, original images are translated into forms that can be used on a printing press, through "color separation" and "screening" or "halftoning." These steps make possible the creation of printing plates that can transfer color impressions to paper on printing presses based on the principles of lithography.

An emerging method of full-color printing is six-color process printing (for example, Pantone's Hexachrome system) which adds orange and green to the traditional CMYK inks for a larger and more vibrant gamut, or color range. However, such alternate color systems still rely on color separation, halftoning and lithography to produce printed images. Within the specialist area of printed packaging, an emerging method of full-color printing is another system, Chapter1, developed by design group LFH. Chapter1 can be tailored to individual companies and was recently adopted by Unilever. It involves the traditional process colors (cyan, magenta and yellow) plus three additional colors chosen to best reproduce a particular company’s range of branded packaging.

Color printing can also involve as few as one color ink, or multiple color inks which are not the primary colors. Using a limited number of color inks, or specific color inks in addition to the primary colors, is referred to as "spot color" printing. Generally, spot-color inks are specific formulations that are designed to print alone, rather than to blend with other inks on the paper to produce various hues and shades. The range of available spot color inks, much like paint, is nearly unlimited, and much more varied than the colors that can be produced by four-color-process printing. Spot-color inks range from subtle pastels to intense fluorescents to reflective metallics.

Color printing involves a series of steps, or transformations, to generate a quality color reproduction. The following sections focus on the steps used when reproducing a color image in CMYK printing, along with some historical perspective.

Digital printing

2008-11-28T00:38:00.000-08:00

Digital printing accounts for approximately 9% of the 45 trillion pages printed (2005 figure) around the world.[8]

Printing at home or in an office or engineering environment is subdivided into:

* small format (up to ledger size paper sheets), as used in business offices and libraries
* wide format (up to 3' or 914mm wide rolls of paper), as used in drafting and design establishments.

Some of the more common printing technologies are:

* blueprint—and related chemical technologies.
* daisy wheel—where pre-formed characters are applied individually.
* dot-matrix—which produces arbitrary patterns of dots with an array of printing studs.
* inkjet—including bubble-jet—where ink is sprayed onto the paper to create the desired image.
* laser—where toner consisting primarily of polymer with pigment of the desired colours is melted and applied directly to the paper to create the desired image.
* line printing—where pre-formed characters are applied to the paper by lines.
* heat transfer—like early fax machines or modern receipt printers that apply heat to special paper, which turns black to form the printed image.

Vendors typically stress the total cost to operate the equipment, involving complex calculations that include all cost factors involved in the operation as well as the capital equipment costs, amortization, etc. For the most part, toner systems beat inkjet in the long run, whereas inkjets are less expensive in the initial purchase price.

Professional digital printing (using toner) primarily uses an electrical charge to transfer toner or liquid ink to the substrate it is printed on. Digital print quality has steadily improved from early color and black & white copiers to sophisticated colour digital presses like the Xerox iGen3, the Kodak Nexpress, the HP Indigo Digital Press series and the InfoPrint 5000. The iGen3 and Nexpress use toner particles and the Indigo uses liquid ink. The InfoPrint 5000 is a full-color, continuous forms inkjet drop-on-demand printing system. All handle variable data and rival offset in quality. Digital offset presses are called direct imaging presses; although these receive computer files and automatically turn them into print-ready plates, they cannot insert variable data.

Small press and fanzines generally use digital printing or more rarely xerography. Prior to the introduction of cheap photocopying the use of machines such as the spirit duplicator, hectograph, and mimeograph was common.

Religious impact

2008-11-28T00:36:00.000-08:00

Samuel Hartlib, who was exiled in Britain and enthusiastic about social and cultural reforms, wrote in 1641 that "the art of printing will so spread knowledge that the common people, knowing their own rights and liberties, will not be governed by way of oppression".[9] For both churchmen and governments, it was concerning that print allowed readers, eventually including those from all classes of society, to study religious texts and politically sensitive issues by themselves, instead of thinking mediated by the religious and political authorities.

It took a long long time for print to penetrate Russia and the Orthodox Christian world, a region (including modern Serbia, Romania and Bulgaria) where reading ability was largely restricted to the clergy. In 1564, a White Russian brought a press to Moscow, and soon after that his workshop was destroyed by a mob.

In the Muslim world, printing, especially in Arabic or Turkish was strongly opposed throughout the early modern period (printing in Hebrew was sometimes permitted). Indeed, the Muslim countries have been regarded as a barrier to the passage of printing from China to the West. According to an imperial ambassador to Istanbul in the middle of the sixteenth century, it was a sin for the Turks to print religious books. In 1515, Sultan Selim I issued a decree under which the practice of printing would be punishable by death. At the end of the century, Sultan Murad III permitted the sale of non-religious printed books in Arabic characters, yet the majority were imported from Italy.

It was thought that the introduction of the printing medium 'would strengthen religion and enhance the power of monarchs.' [10] The majority of books were of religious nature with the church and crown regulating the content. The consequences of printing wrong material were extreme. Meyrowitz [11] used the example of William Carter who, in 1584, printed a pro-Catholic pamphlet in Protestant-dominated England. The consequence of his action was hanging.

The widespread distribution of the Bible 'had a revolutionary impact, because it decreased the power of the Catholic Church as the prime possessor and interpretor of God's word.' [12]

Offset press

2008-11-22T13:06:00.003-08:00

Offset printing is a widely used printing technique where the inked image is transferred (or "offset") from a plate to a rubber blanket, then to the printing surface. When used in combination with the lithographic process, which is based on the repulsion of oil and water, the offset technique employs a flat (planographic) image carrier on which the image to be printed obtains ink from ink rollers, while the non-printing area attracts a film of water, keeping the non-printing areas ink-free.

Currently, most books and newspapers are printed using the technique of offset lithography. Other common techniques include:

* flexography used for packaging, labels, newspapers.
* hot wax dye transfer
* inkjet used typically to print a small number of books or packaging, and also to print a variety of materials from high quality papers simulate offset printing, to floor tiles; Inkjet is also used to apply mailing addresses to direct mail pieces.
* laser printing mainly used in offices and for transactional printing (bills, bank documents). Laser printing is commonly used by direct mail companies to create variable data letters or coupons, for example.
* pad printing popular for its unique ability to print on complex 3-dimensional surfaces.
* relief print, (mainly used for catalogues).
* rotogravure mainly used for magazines and packaging.
* screen printing from T-shirts to floor tiles.

Modern printing technology

2008-11-22T13:06:00.001-08:00

Across the world, over 45 trillion pages (2005 figure) are printed annually.[8] In 2006 there were approximately 30,700 printing companies in the United States, accounting for $112 billion, according to the 2006 U.S. Industry & Market Outlook by Barnes Reports. Print jobs that move through the Internet made up 12.5% of the total U.S. Printing market last year, according to research firm InfoTrend/CAP Ventures.

Movable type printing

2008-11-22T13:05:00.003-08:00

Movable type is the system of printing and typography using movable pieces of metal type, made by casting from matrices struck by letterpunches. Movable type allowed for much more flexible processes than hand copying or block printing.

Around 1040, the first known movable type system was created in China by Bi Sheng out of porcelain.

Around 1450, Johannes Gutenberg introduced what is regarded as an independent invention of movable type in Europe (see printing press), along with innovations in casting the type based on a matrix and hand mould. Gutenberg was the first to create his type pieces from an alloy of lead, tin and antimony – the same components still used today.[5]

Johannes Gutenberg's work on the printing press began in approximately 1436 when he partnered with Andreas Dritzehen — a man he had previously instructed in gem-cutting—and Andreas Heilmann, owner of a paper mill.[6] It was not until a 1439 lawsuit against Gutenberg that official record exists; witnesses testimony discussed type, an inventory of metals (including lead) and his type mold.[6]

Compared to woodblock printing, movable type page setting was quicker and more durable. The metal type pieces were more durable and the lettering was more uniform, leading to typography and fonts. The high quality and relatively low price of the Gutenberg Bible (1455) established the superiority of movable type, and printing presses rapidly spread across Europe, leading up to the Renaissance, and later all around the world. Today, practically all movable type printing ultimately derives from Gutenberg's movable type printing, which is often regarded as the most important invention of the second millennium

In Europe

2008-11-22T13:05:00.001-08:00

Block printing first came to Christian Europe as a method for printing on cloth, where it was common by 1300. Images printed on cloth for religious purposes could be quite large and elaborate, and when paper became relatively easily available, around 1400, the medium transferred very quickly to small woodcut religious images and playing cards printed on paper. These prints were produced in very large numbers from about 1425 onwards.

Around the mid-century, block-books, woodcut books with both text and images, usually carved in the same block, emerged as a cheaper alternative to manuscripts and books printed with movable type. These were all short heavily illustrated works, the bestsellers of the day, repeated in many different block-book versions: the Ars moriendi and the Biblia pauperum were the most common. There is still some controversy among scholars as to whether their introduction preceded or, the majority view, followed the introduction of movable type, with the range of estimated dates being between about 1440–1460

In Islamic world

2008-11-22T13:04:00.003-08:00

Woodblock printing on cloth appeared in Islamic Egypt by the 4th century, though it is not clear if the Egyptian printing of cloth was learned from China or developed separately. Block printing of text, called tarsh in Arabic was developed in Arabic Egypt during the 9th-10th centuries, mostly for prayers and amulets. It is unclear whether the print blocks were made from metal or wood or other materials.[2] This technique, however, appears to have had very little influence outside of the Muslim world. Though Europe adopted woodblock printing from the Muslim world, initially for fabric, the technique of metal block printing was also unknown in Europe. Block printing later went out of use in Islamic Central Asia after movable type printing was introduced from China.

In East Asia

2008-11-22T13:04:00.001-08:00

By 593 A.D., the first printing press was invented in China, and the first printed newspaper was available in Beijing in 700 A.D. It was a woodblock printing. And the Tianemmen scrolls, the earliest known complete woodblock printed book with illustrations was printed in China in 868 A.D. And Chinese printer Bi Sheng invented movable type in 1041 A.D. in China[1]. Sheng used clay type, which broke easily, but Wang Zhen later carved a more durable type from wood by 1298 AD, and developed a complex system of revolving tables and number-association with written Chinese characters that made typesetting and printing more efficient.

Woodblock printing

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Woodblock printing is a technique for printing a text, images or patterns that was used widely throughout East Asia. It originated in China in antiquity as a method of printing on textiles and later on paper. As a method of printing on cloth, the earliest surviving examples from China date to before 220, and from Egypt to the 4th century.

Intaglio rotogravure printing machine

2008-11-21T08:22:00.000-08:00

This machine is used for BOPP,PET,PVC,PE Rolling Paper etc with good printing performance
of rolling material for multi-color continuous printing.
FEATURE:
1.360-degree printing plate aligning device ,easy operation.
2.Dual-drying tunnel farinfrared fire tube heating system.
3.Magnetic powder brake control for unreeling tension system, reeling with moment
motor.
4.Reeling in and unreeling at dual stations,semi-automatic material change without
machine halt.
5.One-off printing on both sides.
Model ASY-600/6colors ASY-800/6colors ASY-1000/6colorscolors
Length of Printing 220mm-850mm 220mm-850mm 220mm-850mm
Width of Printing 600mm 800mm 1000mm
Speed of Printing 10-50mm 10-50mm 10-50mm
Accuracy of Registration 0.2mm 0.2mm 0.2mm
Total Power 18kw 22kw 26kw
Net weight:
Overall Dimentions(L/W/H) 8500/1700/2000mm 8500/1900/2000mm 8500/2200/2000mm

http://www.alibaba.com/showroom/Printing_Machine/--2309------------------------.html?noddp=Y

YT series Six-Color Flexography Printing Machine

2008-11-21T08:18:00.000-08:00

Features Specifications: YT series Six-Color Flexography Printing Machine

Features:
1) Easy operation, flexible starting, accurate color register
2) The meter counter can set printing quantity according to the requirements, stop the machine automatically at the quantity or when the material is cut off
3) Pneumatic printing cylinder lift and lower, it will stir the printing ink automatically after lifting
4) The printing ink is spread by the anilox cylinder with even ink color
5) Due to the reliable drying system coordinated with high-speed rotation, it will automatically break circuit when the machine stops
6) 360 degrees continuous and adjustable longitudinal register device
7) The frequency control of motor speed adapts to different printing speeds
8) There are jogging / stopping buttons on the plate roller base and material rolling rack so as to make it easy to operate the machine when the plate is installed
9) Application: introducing sensitization resin as flexible printing plate, it is suitable for printing such packing materials as polyethylene, polypropylene bag, and cellophane and roll paper. It is a kind of ideal printing equipment for producing paper packing bag for food, supermarket handbags, vest bags and clothes bags.

http://www.alibaba.com/product-gs/201565257/YT_series_Six_Color_Flexography_Printing.html

Flexo Printing Machine

2008-11-21T08:15:00.000-08:00

Station for 5-color flexo printing machine:

1.One Paste plate machine
2.One anilox roller for each group (LPI is optional, made in shanghai)
3.Three sets printing rollers
4.Printing both sides at the same time (with Reverse frame)
5.With the lamination station
6.One unwinding tension controller (Mitsubishi Japan)
7.One rewinding tension controller
8.magnetic power brake (made in Ningxia China)
9.Frequency changer (Taida)
10.Mainframe: 2.2KW (Mindong)

http://www.alibaba.com/product-gs/202322611/Flexo_Printing_Machine.html

Gravure Printing Machine

2008-11-21T08:13:00.000-08:00

Model:ASY-6800
Printing width(mm):800
Speed of printing(m/min):≤60
Diameter of printing cylinder:50-380
Printing color number:1-6
Gross power(kw):26
Installing dimensions(LxWxH)(mm):8700x1800x2200
Weight(kg):6600

http://www.alibaba.com/product-gs/51726701/Gravure_Printing_Machine.html

ZBS-320 Flexo Printing Machine

2008-11-21T08:10:00.000-08:00

This type of printing machine is suitable for printing roll paper or label paper and film. It can finish printing, UV varnishing, infrared drying, film laminating, rotary die cutting and rewinding (according to customers' requirements). Main machine is frequency inverter control, tension control by magnetic powder with Japan tension controller.
The mechanism structure is compact and easy to operate and save space (overlap type).

Specifications:
1) Printing speed: 5 - 50m/min
2) Print color: 4 colors (5 or 6 color)
3) Flexo plate thickness: 1.7mm
4) Thickness of double adhesive tape: 0.38mm
5) Max. diameter of unwinding: 600mm
6) Max. diameter of rewinding: 550mm
7) Max. printing circumference: 323.85mm(or custom-built)
8) Min. printing circumference: 177.8mm
9) Color register precision: less than 0.15mm
10) Main motor power: 2.2kW
11) Total: 6.8kW(according to different requirement)
12) Power voltage: 380V,50HZ(or special make)
13) Overall dimensions: 2 x 1.1 x 2.1m
14) Machine weight: about 2000kg

http://www.alibaba.com/product-gs/200850270/ZBS_320_Flexo_Printing_Machine.html

Flexography Printing Machine

2008-11-21T08:07:00.000-08:00

Brief Introduction:

1. Printing materials: nonwoven, paper, PE, PP, OPP, BOPP, tissue and other web rolls
2. Both sides printing.
3. Variable frequency drive for regulation. Power saving and easy operation.
4. All pulling rollers are made of stainless steel to insure top dynamic balance.
5. Print cylinders are locked up in steel clumps, eliminating print cylinder bounce. Plate is fixed by self adhesive tapes.
6. Print impression and ink delivery operate independently, allowing the operator to always set a perfect kiss impression for better print quality.

http://www.alibaba.com/product-gs/51849716/Flexography_Printing_Machine.html

ZH-800/800C/800/1000 Automatic Folder Gluer

2008-11-21T08:05:00.000-08:00

PRODUCT INTRODUCTION

Model ZH-800 is the companys main push ordinary type folder gluer, its stability, versatility and flexibility are uses praise. Small to large box can paste. For small boxes, it can make 40,000 to 50,000 pcs per hour It is an Ideal equipment for printing industry.

http://www.alibaba.com/product-gs/210348891/ZH_800_800C_800_1000_Automatic.html

Four-Color Flexography Printing Machine

2008-11-21T08:03:00.001-08:00

Features Specifications: Four-Color Flexography Printing Machine
Features:
1) Easy operation, flexible starting, accurate color register
2) The meter counter can set printing quantity according to the requirements
3) Stops automatically at the quantity or when the material is cut off
4) Pneumatic printing cylinder lift and lower, it will stir the printing ink
automatically after lifting
5) The printing ink is spread by the anilox cylinder with even ink color
6) Reliable drying system coordinated with high-speed rotation, it will
automatically break circuit when machine stops
6) 360 degrees continuous and adjustable longitudinal register device
7) The frequency control of motor speed adapts to different printing speeds
8) With jogging / stopping buttons on plate roller base and material rolling
rack so as to make it easy to operate the machine when plate is installed
9) Introducing sensitization resin as flexible printing plate, it is suitable for
printing such packing materials as polyethylene, polypropylene, cellophane
and roll paper
10) A kind of ideal printing equipment for producing paper packing bags for
food, supermarket handbags, vest bags, clothes bags and industrial
products

http://www.alibaba.com/product-gs/50373289/Four_Color_Flexography_Printing_Machine.html

Label Flexo Printing Machine

2008-11-21T08:00:00.000-08:00

Features:
1) Adopts ceramic wave roller to spread black
2) Webbing and winding controlled by magnetic power brake, clutch or automatic
tension controller from Mitsubishi of Japan
3) Print unit adopts 3,600 week to regulate to each edition
4) Print unit has one infrared to dry the device group each
5) The black roller can break away automatically while parking, and running
at a low speed, in order to avoid water being black to dry
6) The main motor adopts the stepless regulation of frequency conversion
7) Supports paper from tube material, print, have light, dry automatically
by infrared ray, punching, film compounding, and winding completed in one
operation
8) Ideal for printing houses to print trade invoices and dry adhesive tape

http://www.alibaba.com/product-gs/50205542/Label_Flexo_Printing_Machine.html

Bestech Sheet-Fed Offset Press

2008-11-21T07:55:00.000-08:00

Main Specifications:
1) Printing speed: 13,000 sheets/h
2) Max. sheet size: 720 x 1,020mm
3) Min. sheet size: 360 x 540mm
4) Max. image area: 710 x 1,020mm
5) Paper thickness: 0.04 - 0.6mm
6) Plate size: 800 x 1,030mm
7) Blankeet size: 975 x 1,035mm
8) Max. feeder pile height: 1,150mm
9) Max. delivery pile height: 1,150mm
10) Press weight: 33,900kg
11) Overall dimensions (L x W x H): 8,200 x 3,490 x 2,400mm
12) Total power: 75kW

http://www.alibaba.com/product-gs/50418701/Bestech_Sheet_Fed_Offset_Press.html