Silk screening or "Screen Printing" can be traced to China and Japan as far back as, 960-1280 AD. In the very beginning silk screen printers actually made screens out of human hair. The silk screen inks that were used were made from dyes in berries and vegetation. 

In 1907 in Manchester England, Samuel Simon receives a patent for using a silk screen fabric as a printing screen, thus the modern version of silk screening is born. 

Years ago silkscreen became obsolete in the screen making process, and was replaced by synthetic threads. Although many people refer to it as silk screening, it is primarily known now as just screen printing. 

The screen itself contains interwoven threads that create small holes between the weaves. 
Mesh counts are categorized by these holes, I.E. a 110 mesh has 110 small holes per square inch, thus a 155 mesh would have 155 holes, a 305 mesh, 305 holes and so on. 
In other words the higher number of screen mesh will yield a higher resolution screen print. 

Basically the screen printing mesh comes primarily on a wood frame or an aluminum screen frame, where it is stretched taut and then glued to the frame. The preparation of the screen to be print ready is to first de-grease the screen and after drying, to coat the screen with a photo sensitive emulsion. It is then exposed to a UV specific light source; also know as an exposure box, or exposure unit with a film positive screen that has been output on to a transparency sheet. 

After washing out with water, you are left with your silk screen image, or screen print image if you prefer, ready to be screen printed. 

The silk screen is then placed onto a screen printing press and aligned with multiple colors; a screen printing press can come in a 1-color, 2-color, 4-color, 6-color, 8-color and so on. 

After placing either solvent based ink or plastisol screen printing ink on the screen, an ink squeegee is used to transfer the ink through the image on the screen, to the substrate you are printing on. 

Silk screens are re-usable as well by taking off your stencil with emulsion remover, and perhaps a haze remover, and then re-coating with the emulsion and starting the process over. 

There are thousands of commonly used consumer products that are screen printed. White t-shirt screen printing is one of the most widely known silk screening forms; screen printing is also used for sign, sticker, wood, glass, and metal applications. Since these products are all in great consumer demand, screen printing has become a very large and profitable business. Starting a silk screening or screen printing business is a great way to create a viable income right out of your own home. 

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