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Screen printing is a printing technique where a mesh is used to transfer ink (or dye) onto a substrate, except in areas made impermeable to the ink by a blocking stencil. A blade or squeegee is moved across the screen in a "flood stroke" to fill the open mesh apertures with ink, and a reverse stroke then causes the screen to touch the substrate momentarily along a line of contact. This causes the ink to wet the substrate and be pulled out of the mesh apertures as the screen springs back after the blade has passed. One colour is printed at a time, so several screens can be used to produce a multi-coloured image or design.
Traditionally, silk was used in the process. Currently, synthetic threads are commonly used. The most popular mesh in general use is made of polyester. There are special-use mesh materials of nylon and stainless steel available to the screen-printer. There are also different types of mesh size which will determine the outcome and look of the finished design on the material.
The technique is used not only for garment printing but for printing on many other substances, including decals, clock and watch faces, balloons, and many other products. Advanced uses include laying down conductors and resistors in multi-layer circuits using thin ceramic layers as the substrate.
Screen printing first appeared in a recognizable form in China during the Song dynasty (960–1279 AD). [1] [2] It was then adapted by other Asian countries like Japan, and was further created using newer methods.
Screen printing was largely introduced to Western Europe from Asia sometime in the late 18th century, but did not gain large acceptance or use in Europe until silk mesh was more available for trade from the east and a profitable outlet for the medium discovered.
Early in the 1910s, several printers experimenting with photo-reactive chemicals used the well-known actinic light–activated cross linking or hardening traits of potassium, sodium or ammonium chromate and dichromate chemicals with glues and gelatin compounds. Roy Beck, Charles Peter and Edward Owens studied and experimented with chromic acid salt sensitized emulsions for photo-reactive stencils. This trio of developers would prove to revolutionize the commercial screen printing industry by introducing photo-imaged stencils to the industry, though the acceptance of this method would take many years. Commercial screen printing now uses sensitizers far safer and less toxic than bichromates. Currently,[ when? ] there are large selections of pre-sensitized and "user mixed" sensitized emulsion chemicals for creating photo-reactive stencils.
A group of artists who later formed the National Serigraph Society, including WPA artists Max Arthur Cohn, Anthony Velonis and Hyman Warsager, coined the word "serigraphy" in the 1930s to differentiate the artistic application of screen printing from the industrial use of the process. [3] "Serigraphy" is a compound word formed from Latin "sēricum" (silk) and Greek "graphein" (to write or draw). [4]
Historians of the New York WPA poster shop give sole credit to Anthony Velonis for establishing Silkscreen methods used there, a reputation bolstered by the publication of his 1937 booklet Technical Problems of the Artist: Technique of the Silkscreen Process. Guido Lengweiler has corrected this misunderstanding in his book, A History of Screen Printing, published in English in 2016. Outgrowths of these WPA poster shops, at least two New York City studios in wartime started decorating ceramic tiles with fire-on underglaze applied by silkscreen starting as early as 1939: Esteban Soriano and Harold Ambellan's workshop called Designed Tiles. [5]
The Printers' National Environmental Assistance Center says, "Screenprinting is arguably the most versatile of all printing processes. Since rudimentary screenprinting materials are so affordable and readily available, it has been used frequently in underground settings and subcultures, and the non-professional look of such DIY culture screenprints have become a significant cultural aesthetic seen on movie posters, record album covers, flyers, shirts, commercial fonts in advertising, in artwork and elsewhere.[ verify ]
Credit is given to the artist Andy Warhol for popularising screen printing as an artistic technique. Warhol's silk screens include his 1962 Marilyn Diptych, which is a portrait of the actress Marilyn Monroe printed in bold colours. Warhol was supported in his production by master screen printer Michel Caza, a founding member of Fespa. [6] [7]
Sister Mary Corita Kent gained international fame for her vibrant serigraphs during the 1960s and 1970s. Her works were rainbow coloured, contained words that were both political, and fostered peace and love and caring.
American entrepreneur, artist and inventor Michael Vasilantone started to use, develop, and sell a rotatable multicolour garment screen printing machine in 1960. Vasilantone later filed for a patent [8] on his invention in 1967 granted number 3,427,964 on 18 February 1969. [8] The original machine was manufactured to print logos and team information on bowling garments, but was soon directed to the new fad of printing on T-shirts. The Vasilantone patent was licensed by multiple manufacturers and the resulting production and boom in printed T-shirts made this garment screen printing machine popular. Screen printing on garments currently[ when? ] accounts for over half of the screen printing activity in the United States. [9]
Graphic screen-printing is widely used today to create mass- or large-batch produced graphics, such as posters or display stands. Full colour prints can be created by printing in CMYK (cyan, magenta, yellow and black).
Screen printing lends itself well to printing on canvas. Andy Warhol, Arthur Okamura, Robert Rauschenberg, Roy Lichtenstein, Harry Gottlieb and many other artists have used screen printing as an expression of creativity and artistic vision.
Another variation, digital hybrid screen printing, is a union between analog screen printing and traditional digital direct-to-garment printing, two of the most common textile embellishment technologies in use today. Essentially, digital hybrid screen printing is an automatic screen-printing press with a CMYK digital enhancement located on one of the screen print stations. Digital hybrid screen printing is capable of variable data options, creating endless customizations, with the added ability of screen print specific techniques.
A screen is made of a piece of mesh stretched over a frame. The mesh could be made of a synthetic polymer, such as nylon, and a finer and smaller aperture for the mesh would be utilized for a design that requires a higher and more delicate degree of detail. For the mesh to be effective, it must be mounted on a frame and it must be under tension. The frame which holds the mesh could be made of diverse materials, such as wood, metal, or aluminum, depending on the sophistication of the machine or the artisan procedure. The tension of the mesh may be checked by using a tensiometer; a common unit for the measurement of the tension of the mesh is Newton per centimeter (N/cm).
A stencil is formed by blocking off parts of the screen in the negative image of the design to be printed; that is, the open spaces are where the ink will appear on the substrate.
Before printing occurs, the frame and screen must undergo the pre-press process, in which an emulsion is 'scooped' across the mesh. Once this emulsion has dried, it is selectively exposed to ultra-violet light, through a film printed with the required design. This hardens the emulsion in the exposed areas but leaves the unexposed parts soft. They are then washed away using a water spray, leaving behind a clean area in the mesh with the identical shape as the desired image, which will allow passage of ink. It is a positive process.
In fabric printing, the surface supporting the fabric to be printed (commonly referred to as a pallet) is coated with a wide 'pallet tape'. This serves to protect the 'pallet' from any unwanted ink leaking through the screen and potentially staining the 'pallet' or transferring unwanted ink onto the next substrate. The pallet tape is also used to protect the pallet from the usage of glue that keeps the substrate adhered and in place on the pallet. Over time the pallet tape will become covered with lint which it then can be removed, discarded, and replaced by new pallet tape.
Next, the screen and frame are lined with a tape to prevent ink from reaching the edge of the screen and the frame. The type of tape used in for this purpose often depends upon the ink that is to be printed onto the substrate. More aggressive tapes are generally used for UV and water-based inks due to the inks' lower viscosities and greater tendency to creep underneath tape.
The last process in the 'pre-press' is blocking out any unwanted 'pin-holes' in the emulsion. If these holes are left in the emulsion, the ink will continue through and leave unwanted marks. To block out these holes, materials such as tapes, speciality emulsions and 'block-out pens' may be used effectively.
The screen is placed atop a substrate. Ink is placed on top of the screen, and a floodbar is used to push the ink through the holes in the mesh. The operator begins with the fill bar at the rear of the screen and behind a reservoir of ink. The operator lifts the screen to prevent contact with the substrate and then using a slight amount of downward force pulls the fill bar to the front of the screen. This effectively fills the mesh openings with ink and moves the ink reservoir to the front of the screen. The operator then uses a squeegee (rubber blade) to move the mesh down to the substrate and pushes the squeegee to the rear of the screen. The ink that is in the mesh opening is pumped or squeezed by capillary action to the substrate in a controlled and prescribed amount, i.e. the wet ink deposit is proportional to the thickness of the mesh and or stencil. As the squeegee moves toward the rear of the screen the tension of the mesh pulls the mesh up away from the substrate (called snap-off) leaving the ink upon the substrate surface.
There are three common types of screen printing presses: flat-bed, cylinder, and rotary. [10] A development of screen printing with flat screens from 1963 was to wrap the screen around to form a tube, with the ink supply and squeegee inside the tube. The resulting roller rotates at the same speed as the web in a roll-to-roll machine. The benefits are high output rates and long rolls of product. This is the only way to make high-build fully patterned printing/coating as a continuous process, and has been widely used for manufacturing textured wallpapers.
Textile items printed with multi-coloured designs often use a wet on wet technique, or colours dried while on the press, while graphic items are allowed to dry between colours that are then printed with another screen and often in a different colour after the product is re-aligned on the press.
Most screens are ready for re-coating at this stage, but sometimes screens will have to undergo a further step in the reclaiming process called de-hazing. This additional step removes haze or "ghost images" left behind in the screen once the emulsion has been removed. Ghost images tend to faintly outline the open areas of previous stencils, hence the name. They are the result of ink residue trapped in the mesh, often in the knuckles of the mesh (the points where threads cross). A properly cleaned screen will not have any residual traces of the previous image apparent on its surface.
A method of stenciling that has increased in popularity over the past years is the photo emulsion technique:
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Screen printing is more versatile than traditional printing techniques. The surface does not have to be printed under pressure, unlike etching or lithography, and it does not have to be planar. Different inks can be used to work with a variety of materials, such as textiles, ceramics, [13] wood, paper, glass, metal, and plastic. As a result, screen printing is used in many different industries, including:
In screen printing on wafer-based solar photovoltaic (PV) cells, the mesh and buses of silver are printed on the front; furthermore, the buses of silver are printed on the back. Subsequently, aluminum paste is dispensed over the whole surface of the back for passivation and surface reflection. One of the parameters that can vary and can be controlled in screen printing is the thickness of the print. This makes it useful for some of the techniques of printing solar cells, electronics etc.
Solar wafers are becoming thinner and larger, so careful printing is required to maintain a lower breakage rate, though high throughput at the printing stage improves the throughput of the whole cell production line.
To print multiple copies of the screen design on garments in an efficient manner, amateur and professional printers usually use a screen printing press, which is a colloquial term as most screen printing machines are vastly different from offset printing presses. Many companies offer simple to sophisticated printing presses. These presses come in one of three types, manual (also referred to as handbench), semi-automatic, and fully automatic. Most printing companies will use one or more semi-automatic or fully automatic machines with manual machines for small runs and sampling.
Whilst manual screen printing can be done with carousels, handbenches (both of which are often referred to colloquially as presses) or even on to tables. Semi- and fully-automatic machines are broken into two main categories; flatbed printers [17] (poster, art printing or other flat substrates) and carousels and oval machines (garments and other apparel, amongst other textiles). Both which are fundamentally similar in terms of automation but differ in areas such as physical footprint and upgrade paths. [18]
These machines are much faster and use either pneumatic pressure generated by air compressors or use electric motors to draw the squeegees, rotate and raise or lower pallets removing much of the manual labour from the task and use UV for instant image curing - resulting in significant reductions in operator fatigue as well as more consistent results. [19]
In electronic design automation, the silk screen is part of the layer stack of the printed circuit board (PCB), and the top and bottom sides are described in individual Gerber files like any other layers (such as the copper and solder-stop layers). [20] Typical names for these service print overlays include tSilk
/bSilk
aka PLC
/PLS
[21] [nb 1] or TSK
/BSK
(EAGLE), F.SilkS
/B.SilkS
(KiCad), PosiTop
/PosiBot
(TARGET), silkTop
/silkBottom
(Fritzing), SST
/SSB
(OrCAD), ST.PHO
/SB.PHO
(PADS), SEVS
/SERS
(WEdirekt) [22] or GTO
/GBO
(Gerber and many others [23] ).
Screen printing, a widely adopted technique in the printing industry, has found its niche in the realm of printed electronics. Its versatility and ability to deposit thick layers of inks make it ideal for creating conductive tracks, sensors, and other electronic components. Furthermore, screen printing offers advantages such as high throughput, low production costs, and compatibility with a wide range of substrates, including flexible materials. These attributes make it a preferred choice for large-scale production of printed electronic devices.
While screen printing offers tremendous potential in printed electronics, it also faces certain challenges. Fine-line resolution, compatibility with advanced materials, and the need for precise registration pose ongoing research and development opportunities. However, continuous advancements in ink formulations, equipment, and process optimization are paving the way for exciting future possibilities, including the integration of printed electronics into Internet of Things (IoT) devices, energy harvesting systems, and more.
.PLC
/.PLS
for the top and bottom silk screens have their origin in times when printed circuit boards were typically equipped with components populated on one side of the board only, the so called "component side" (top) versus the opposite "solder side" (bottom) where these components were soldered (at least in the case of through-hole components). Each silk screen layer is often a combination of the corresponding Place and Names layers (and the Dimension layer), thus the 'PL' in the filename extension.Lithography is a planographic method of printing originally based on the immiscibility of oil and water. The printing is from a stone or a metal plate with a smooth surface. It was invented in 1796 by the German author and actor Alois Senefelder and was initially used mostly for musical scores and maps. Lithography can be used to print text or images onto paper or other suitable material. A lithograph is something printed by lithography, but this term is only used for fine art prints and some other, mostly older, types of printed matter, not for those made by modern commercial lithography.
A mimeograph machine was a low-cost duplicating machine that worked by forcing ink through a stencil onto paper. The process was called mimeography, and a copy made by the process was a mimeograph.
Printmaking is the process of creating artworks by printing, normally on paper, but also on fabric, wood, metal, and other surfaces. "Traditional printmaking" normally covers only the process of creating prints using a hand processed technique, rather than a photographic reproduction of a visual artwork which would be printed using an electronic machine ; however, there is some cross-over between traditional and digital printmaking, including risograph.
Dye-sublimation printing is a term that covers several distinct digital computer printing techniques that involve using heat to transfer dye onto a substrate.
A T-shirt is a style of fabric shirt named after the T shape of its body and sleeves. Traditionally, it has short sleeves and a round neckline, known as a crew neck, which lacks a collar. T-shirts are generally made of stretchy, light, and inexpensive fabric and are easy to clean. The T-shirt evolved from undergarments used in the 19th century and, in the mid-20th century, transitioned from undergarments to general-use casual clothing.
Stencilling produces an image or pattern on a surface by applying pigment to a surface through an intermediate object, with designed holes in the intermediate object. The holes allow the pigment to reach only some parts of the surface creating the design. The stencil is both the resulting image or pattern and the intermediate object; the context in which stencil is used makes clear which meaning is intended. In practice, the (object) stencil is usually a thin sheet of material, such as paper, plastic, wood or metal, with letters or a design cut from it, used to produce the letters or design on an underlying surface by applying pigment through the cut-out holes in the material.
Rotogravure is a type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset printing and flexography, it uses a rotary printing press.
Iron-on transfers are images that can be imprinted on fabric. They are frequently used to print onto T-shirts.
Textile printing is the process of applying color to fabric in definite patterns or designs. In properly printed fabrics the colour is bonded with the fibre, so as to resist washing and friction. Textile printing is related to dyeing but in dyeing properly the whole fabric is uniformly covered with one colour, whereas in printing one or more colours are applied to it in certain parts only, and in sharply defined patterns.
Print Gocco was a compact, self-contained card printing system developed by Riso Kagaku Corporation and first sold in 1977. Print Gocco achieved significant success and sold over 10 million units cumulatively before production ceased in 2008.
Vinyl banners are a form of banners made of vinyl. The most commonly used material is PVC. Most banners are now digitally printed on large format inkjet printers which are capable of printing a full color outdoor billboard on a single piece of material. They are used for outdoor advertising.
The history of printing starts as early as 3000 BCE, when the proto-Elamite and Sumerian civilizations used cylinder seals to certify documents written in clay tablets. Other early forms include block seals, hammered coinage, pottery imprints, and cloth printing. Initially a method of printing patterns on cloth such as silk, woodblock printing for texts on paper originated in China by the 7th century during the Tang dynasty, to the spread of book production and woodblock printing in other parts of Asia such as Korea and Japan. The Chinese Buddhist Diamond Sutra, printed by woodblock on 11 May 868, is the earliest known printed book with a precise publishing date. Movable type was invented by Chinese artisan Bi Sheng in the 11th century during the Song dynasty, but it received limited use compared to woodblock printing. However, the use of copper movable types was documented in a Song-era book from 1193, and the earliest printed paper money using movable metal type to print the identifying codes were made in 1161. The technology also spread outside China, with the oldest extant printed book using metal movable type being the Jikji, printed in Korea in 1377 during the Goryeo era.
Transfer paper is used in textiles and arts and crafts projects. Transfer paper is a thin piece of paper coated with wax and pigment. Often, an ink-jet or other printer is used to print the image on the transfer paper. A heat press can transfer the image onto clothing, canvas, or other surface. Transfer paper is used in creating iron-ons. Transfer papers can also be used for the application of rhinestones to clothing and other arts and crafts projects.
Thick-film technology is used to produce electronic devices/modules such as surface mount devices modules, hybrid integrated circuits, heating elements, integrated passive devices and sensors. The main manufacturing technique is screen printing (stenciling), which in addition to use in manufacturing electronic devices can also be used for various graphic reproduction targets. It became one of the key manufacturing/miniaturisation techniques of electronic devices/modules during 1950s. Typical film thickness – manufactured with thick film manufacturing processes for electronic devices – is 0.0001 to 0.1 mm.
Direct-to-garment printing (DTG) is a process of printing on textiles using specialized aqueous ink jet technology. DTG printers typically have a platen designed to hold the garment in a fixed position, and the printer inks are jetted or sprayed onto the textile by the print head. DTG typically requires that the garment be pre-treated with a PTM or pre-treatment machine, allowing for the following:
Digital ceramic printing on glass is a technological development used for the application of imagery, pattern or text to the surface of flat glass. Like other printing on glass methods, it uses a form of printmaking. Digital ceramic printing on glass has allowed for new possibilities and improvements in flat glass decoration and treatment such as high levels of customization, translucency and opacity control, light diffusion and transmission, ability to calculate solar heat gain co-efficiency, electrical conductivity, slip resistance, and reduced occurences of bird collision.
A contact copier is a device used to copy an image by illuminating a film negative with the image in direct contact with a photosensitive surface. The more common processes are negative, where clear areas in the original produce an opaque or hardened photosensitive surface, but positive processes are available. The light source is usually an actinic bulb internal or external to the device
Heat transfer vinyl (HTV) is a speciality polyurethane with a heat-activated adhesive that can be used on certain fabrics and materials to apply designs to promotional products, textiles and apparel, such as T-shirts. It comes laminated together with a clear polyester carrier in a roll or sheet form, with an adhesive tacky backing, so it can be cut, weeded, and placed on a substrate for application via a heat press. The design is cut into the material with a cutting plotter in reverse. The excess material is removed with tools such as hooks or tweezers - a manual and dextrous process referred to as "weeding". The tacky adhesive between the carrier and the vinyl holds together complex designs, although the labour naturally increases the more weeding that is required. The clear polyester carrier keeps the design visible to aid positioning on the substrate. For these and other reasons, it is a popular and more robust alternative to transfer paper. Heat transfer vinyl is made in single colors and also has special options such as patterned, glitter, flocked, holographic, glow-in-the-dark, reflective and 3D puff. Heat transfer vinyl also benefits from a high degree of stretch and rebound, achieved by a memory effect, making it suitable for use on apparel and other flexible items including the garments typically used, such as sports jerseys.
The Marilyn Monroe portfolio is a portfolio or series of ten 36×36 inch silkscreened prints on paper by the pop artist Andy Warhol, first made in 1967, all showing the same image of the 1950s film star Marilyn Monroe but all in different, mostly very bright, colors. They were made five years after her death in 1962. The original image was taken by Warhol from a promotional still by Gene Kornman for Monroe's film Niagara (1953).
Glass printing involves applying images, patterns, or text to glass surfaces. Various techniques can be used, each offering distinct aesthetic and functional results. This specialized field encompasses methods such as screen printing, digital printing, and pad printing, among others. Each technique offers distinct advantages in terms of durability, resolution, and application. Glass printing is used in numerous industries, including architecture, automotive, interior design, and consumer electronics, where it is valued for its aesthetic appeal, functionality, and ability to enhance the visual and physical properties of glass products. Technological advances have expanded the possibilities of glass printing, allowing for intricate designs, vibrant colors, and improved adhesion, making it an integral part of modern manufacturing and design.