Screen-printing, silkscreening, or serigraphy is a printmaking technique that creates a sharp-edged image by passing ink past a stencil attached to a woven mesh. A screenprint or serigraph is an image created using this technique.
Contents

    * 1 History
    * 2 Printing technique
    * 3 Stenciling techniques
    * 4 Screenprint methods
    * 5 Versatility
    * 6 External links
    * 7 Notes

History

First appearing in recognizable form in China during the Song Dynasty yeas of 960–1279 CE.

Screen printing was first patented in England by Samuel Simon in 1907, but had been in existence in Western Europe from the late 1700's. Originally a popular method to print expensive wall paper actually printed on linen, silk, and other fine fabrics. Jealously guarded as a valuable trade secret, western screen printers developed reclusive, defensive, and exclusionary business policies focused on secreting shop knowledge and techniques.

Joseph Ulano founded the industry chemical supplier Ulano and in 1928 created a method of applying a lacquer soluble stencil material to a removable base. This stencil material was cut into shapes, the print areas removed and the remaining material adhered to mesh to create a sharp edged screen stencil.

Early in the 1910's several printers experimenting with photo-reactive chemicals used the well known actinic light activated cross linking or hardening traits of potassium, sodium or ammonium bichromate chemicals with glues and gelatin compounds. Roy Beck, Charles Peter and Edward Owens study and experimentation with chromic acid salt sensitized emulsions for photo-reactive stencils revolutionized the commercial screen printing industry. Commercial screen printing now uses sensitizers far safer and less toxic than bichromates, currently there are large selections of pre-sensitized and "user mixed" sensitized emulsion chemicals for creating photo-reactive stencils.

Originally a profitable industrial technology, screen printing was eventually adopted by American graphic art well before the 1900s. Credit is generally given to the artist Andy Warhol for popularizing screen printing identified as serigraphy, in the United States. Mr. Warhol is particularly identified with his 1967 depiction of actress Marilyn Monroe screen printed in garish colors.

It is currently popular both in fine arts and in commercial printing, where it is commonly used to print images on T-shirts, hats, CDs, DVDs, ceramics, glass, polyethylene, polypropylene, paper, metals, and wood. Artist coined the word Serigraphy to differentiate the artistic application of screen printing from the industrial use of the process. "Serigraphy" is a combination word from the Latin word "Seri" (silk) and the Greek word "graphein" (to write or draw).

The Printer's 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, and elsewhere.

Graphic screenprinting is widely used today to create many mass or large batch produced graphics, such as posters or display stands. Full color prints can be created by printing in CMYK (cyan, magenta, yellow and black). Screenprinting is often preferred over other processes such as dye sublimation or inkjet printing because of its low cost and ability to print on many types of media.

In general screen-printing is the process of forcing ink, by pressing with a squeegee, through the mesh of netting of a screen stretch, on a frame, onto the object to be printed. The nonprinting areas of the screen are protected by a mesh cutout stencil or by blocking the mesh areas. This process is also known as serigraphy. Historians were not very sure on where or how this process was discovered and there are many people that contributed to the different processes that we use today.

First I want to mention where printing was developed so that you can get the idea of when this process started. In the 4th Century BC items were found in India. In 300 AD, printing blocks were found in Egyptian burial grounds and Pre-Colombian printed textiles were found in Peru and Mexico.

The first form of screen-printing was seen done by the Polynesian Island natives. They would cut designs into banana leaves and forced dye or ink through the leaf openings. They printed on bark cloth or what they called "tapa." They was these native thought of this process was by watching insects eat holes through leaves and seeing the rain run through the holes.

In 960 —1280 AD in the Sung Dynasty, Japan, Japanese people used screen-printing and were extremely skillful in cutting the stencils. They would hold the pieces of the stencils together by gluing human hair to the stencil. These were called "ties." This was very tedious and time consuming but was very strong and it let the ink pass through it. They used paper made of rice called "rice paper."

In the 1700’s, Englanders also used ties for wallpaper but found it to be very difficult for intricate and detailed designs. So they replaced it with a silk material that was stronger and could be used for more detail. This is how the name silk screen-printing got its name from. Today we use man made fibers like plastic or metal. Screen-printing was a well-guarded secret in the early United States and was sold by traveling teachers to local printers and sign makers. They would pay good money for this knowledge. The reason for this is because there were no patents to protect the works of the inventors. The first item to be made in the United States by using the screen printing process was a felt banner in 1910.

The plates that are used for photographic screen-printing were developed by 5 different men and between the years of 1914 and 1915. Photography was a major contribution to the screen making process. A Frenchman, Louis Jacques Mande Daguerre perfected the method of photography in 1837 who was developed by Nicephore Niepce. He used light to change a chemical coating on a sheet of copper into a picture. He developed this method by bringing out latent or hidden image in the plate. This was called daguerreotypes after him. These pictures could not be duplicated except by re-photographing them and going through the process all over again.

In the early 1930’s Joseph Ulano advanced the screen printing process by developing a spray on lacquer to spray on a hard surface, peel this thin lacquer layer off, cut an image out of the stencil with special tools and apply it to the screen. This process is still used today but there are new materials used rather than lacquer. Silk screen-printing was very sophisticated stencil process. It was developed in 1900 and was first mainly used for advertising and display work. In the 1950, fine artists began to use this process and then this process was then given the name of serigraphy.

Andy Warhol began to use screen-printing to duplicate iconography in the late 20th century. He used a picture of Marilyn Monroe from 1967 and put different color in the highlights of her face, gave the background a red-ish color, tinted her hair a blue and mustard color and her earrings were pink. He then did this process over and over again using different color in each place.

There were many patents that were given to people over time, as this screen printing process became more popular. Samuel Simon of England was granted a patent in 1907 for his "tieless stencil" design, which used coarsely woven silk fabric. This was an extremely intricate design that was glued to fabric. During WWI, screen-printing became a significant part of the industry and high quality signs were made in a short amount of time. An example of this was the "Uncle Sam" posters for recruiting men to the army. In 1924 Joseph Odajian from New York was issued a patent for a stencil apparatus.

There were several organizations once this process was very popular. This first was called the Screen-Printing Process Association, International which was developed in 1948. This association standardized products and motivated good printing. Then in 1965 they changed their name to Screen-Printing Association, International. And in 1973 the Academy of Screen Printing Technology was created for technical authorities to represent the highest technological expertise in screen-printing.

There are seven main types of screen printing processes. They are block, stencil or spray, batik, discharge, resist, photographic and roller machine printing. There are stencils that are used and the oldest on is a hand cut stencil which uses pieces of thin paper that is cut and glued to the underside of the screen. This blocks ink from the non-image area and is very time consuming process and the paper wears out quickly. The thermofax stencil is used in offices for overhear transparencies. Both are fed through a machine and it burns away the image areas. The tusche-and-glue stencil is a special liquid that is painted directly on the stencil and then is coated with special glue. After it dries the tusche is removed and the open areas are ready for ink to pass through. William Henry Fox Talbot discovered that glue, egg albumin and gelatin harden when expose to light and he then created the photographic stencil in 1850. This emulation was light sensitive material that reacted to light and the parts that didn’t receive the light remained soft. When the negative was developed on this photographic paper the areas that received light turned black and the other areas stayed white or turned clear.

There are two basic screen fiber; naturally made fabrics (multifilimant: silk and cotton) and manmade fabrics (monofiliment: polyester). Monofiliment fibers were very smooth so the screen had to roughen prior to the application of the emulsion to that the stencil will adhere. Screens were made of silk gauze, synthetic gauze (nylon, polyester), wire gauze (phosphor, bronze), and a combination (nylon-copper, nylon-bronze).

Early inks were similar to regular paint but today there are different kinds of ink for different applications. For example the ink used for billboards has to be able to withstand the sun, rain, snow and the cold. Glass is grounded up into small crystals and added to ink so that it will reflect when a car light hits it at night. It is very important that there is optimal vicosicy, which is the resistance to flow. It can not be too thick or too thin because a finer mesh needs thinner ink. Egg yoke has a higher vicosity than water for example.

Squeegees are very important too because it is what you use to force the ink through the stencil. It can be made of rubber, plastic or polyurethane depending on what type of ink is used. Vinyl or acetate are water-soluble and will dissolve in water so that type of blade may not be good for water-based ink. The flexibility or hardness of the blade is important too and a Durometer measures it. The harder the blade is the thinner the layer of ink that is applied to the application. There are several types of blades that can be used for different material but all should be held at a 30-degree angle. Some examples of these blades are a single bevel, which is used to print on glass and a round edge, which is used to print on fabrics.

Many years ago wood frames were used for holding the screen printing stencil and fabrics. Today we use steel aluminum frames that will not rust. But such metals are scarce in developing countries and wood frames, with special wood joint, are used. There are many products and careers that are made by the screen printing process. Such things as curtains, banners, towels, plastics, fabrics, awards, cups, truck markings and bumper stickers. Screen-printing has come a long way and we see it’s uses everyday everywhere.

Printing technique

A screen is made of a piece of porous, finely woven fabric (originally silk, but typically made of polyester since the 1940s) stretched over a frame of aluminum or wood. Areas of the screen are blocked off with a non-permeable material to form a stencil, which is a negative of the image to be printed; that is, the open spaces are where the ink will appear.

The screen is placed atop a substrate such as papyrus or fabric. Ink is placed on top of the screen, and a fill bar (also known as a floodbar) is used to fill the mesh openings with ink. 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 transferred by capillary action to the substrate in a controlled and prescribed amount, i.e. the wet ink deposit is equal to the thickness of the stencil. As the squeegee moves toward the rear of the screen the tension of the mesh pulls the mesh up away from the substrate leaving the ink upon the substrate surface.

There are three types of screenprinting presses. The 'flat-bed' (probably the most widely used), 'cylinder', and 'rotary'.[1]

Textile items are printed in multi-color designs using a wet on wet technique, while graphic items are allowed to dry between colors that are then printed with another screen and often in a different color.

The screen can be re-used after cleaning. However if the design is no longer needed, then the screen can be "reclaimed", that is cleared of all emulsion and used again. The reclaiming process involves removing the ink from the screen then spraying on stencil remover to remove all emulsion. Stencil removers come in the form of liquids, gels, or powders. The powdered types have to be mixed with water before use, and so can be considered to belong to the liquid category. After applying the stencil remover the emulsion must be washed out using a pressure washer.

Most screens are ready for recoating at this stage, but sometimes screens will have to undergo a further step in the reclaiming process called dehazing. 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, those points where threads overlap.

While the public thinks of garments in conjunction with screenprinting, the technique is used on tens of thousands of items, decals, clock and watch faces, and many more products. The technique has even been adapted for more advanced uses, such as laying down conductors and resistors in multi-layer circuits using thin ceramic layers as the substrate.

Stenciling techniques
A macro photo of a screenprint with a photographically produced stencil. The ink will be printed where the stencil does not cover the substrate.
A macro photo of a screenprint with a photographically produced stencil. The ink will be printed where the stencil does not cover the substrate.

There are several ways to create a stencil for screenprinting. An early method was to create it by hand in the desired shape, either by cutting the design from a non-porous material and attaching it to the bottom of the screen, or by painting a negative image directly on the screen with a filler material which became impermeable when it dried. For a more painterly technique, the artist would choose to paint the image with drawing fluid, wait for the image to dry, and then coat the entire screen with screen filler. After the filler had dried, water was used to spray out the screen, and only the areas that were painted by the drawing fluid would wash away, leaving a stencil around it. This process enabled the artist to incorporate their hand into the process, to stay true to their drawing.

A method that has increased in popularity over the past 70 years and is tremendously popular is the photo emulsion technique:

   1. The original image is created on a transparent overlay such as acetate or tracing paper. The image may be drawn or painted directly on the overlay, photocopied, or printed with a laser printer, as long as the areas to be inked are opaque. A black-and-white negative may also be used (projected on to the screen). However, unlike traditional platemaking, these screens are normally exposed by using film positives.
   2. The overlay is placed over the emulsion-coated screen, and then exposed with an ultraviolet light source in the 350-420 Nanometer spectrum. Other light sources do not work well. The UV light passes through the clear areas and create a polymerization (hardening) of the emulsion.
   3. The screen is washed off thoroughly. The areas of emulsion that were not exposed to light dissolve and wash away, leaving a negative stencil of the image on the mesh.

Photographic screens can reproduce images with a high level of detail, and can be reused for tens of thousands of copies[citation needed]. The ease of producing transparent overlays from any black-and-white image makes this the most convenient method for artists who are not familiar with other printmaking techniques. Artists can obtain screens, frames, emulsion, and lights separately; there are also preassembled kits, which are especially popular for printing small items such as greeting cards.

Another advantage of screenprinting is that large quantities can be produced rapidly with new automatic presses (up to 1200 shirts in 1 hour).[citation needed] (The record is over 2000 shirts an hour.)

Screenprint methods

Plastisol
    the most common plastisol based print used in garment decoration. Good color opacity onto dark garments and clear graphic detail with, as the name suggests, a more plasticized texture. This print can be made softer with special additives or heavier by adding extra layers of ink. Most plastisol inks require heat (approx. 300 degrees fahrenheit for many inks) to cure the print.

Water-Based inks
    these penetrate the fabric more than the plastisol inks and create a much softer feel. Ideal for printing darker inks onto lighter colored garments. Also useful for larger area prints where texture is important.

PVC/ Phalate Free
    relatively new breed of ink and printing with the benefits of plastisol but without the two main toxic components - soft feeling print.

Discharge inks
    used to print lighter colours onto dark background fabrics, they work by removing the dye in the garment – this means they leave a much softer texture. They are less graphic in nature than plastisol inks, and exact colours are difficult to control, but especially good for distressed and vintage prints.

Foil
    consists of a glue printed onto the fabric and then foil is applied for a mirror finish.

Glitter/Shimmer
    silver flakes are suspended in a plastisol ink to create this sparkle effect. Usually available in gold or silver but can be mixed to make most colours.

Metallic
    similar to glitter, but smaller particles suspended in the ink. A glue is printed onto the fabric then a nanoscale fibers applied on it.

Expanding ink (puff)
    an additive to plastisol inks which raises the print off the garment, creating a 3D feel.

Caviar beads
    again a glue is printed in the shape of the design, to which small plastic beads are then applied – works well with solid block areas creating an interesting tactile surface.

Four color process
    artwork is created using dots (CMYK) which combine to create the full spectrum of colours needed for photographic prints – this means a large number of colors can be printed using only 4 screens, making the set-up costs viable. The inks are required to blend and are more translucent, meaning a compromise with vibrancy of color.

Gloss
    a clear base laid over plastisol inks to create a shiny finish.

Nylobond
    a special ink additive for printing onto technical or waterproof fabrics.

Mirrored silver
    Another solvent based ink but you can almost see your face in it.

Suede Ink
    Suede is another great ink that is easy to print and gives the image a textured leather, simulated suede look and feel. Suede is a milky colored additive (much like a plastisol base) that will work in a regular plastisol. It is actually a puff blowing agent that does not bubble as much as regular puff ink. With suede additive you can make any color of plastisol have a suede feel. The directions vary from manufacturer to manufacturer, but generally you can add up to 50% suede additive to your normal plastisol.

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