Screen printing is a printing technique that uses a woven mesh to support an ink-blocking stencil. The attached stencil forms open areas of mesh that transfer ink or other printable materials which can be pressed through the mesh as a sharp-edged image onto a substrate. A roller or squeegee is moved across the screen stencil, forcing or pumping ink past the threads of the woven mesh in the open areas. Screen printing is also a stencil method of print making in which a design is imposed on a screen of silk or other fine mesh, with blank areas coated with an impermeable substance, and ink is forced through the mesh onto the printing surface. It is also known as silkscreen, seriography, and serigraph. There are various terms used for what is essentially the same technique. Traditionally the process was called screen printing or silkscreen printing because silk was used in the process. Currently, synthetic threads are commonly used in the screen printing process. 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. Screen printing first appeared in a recognizable form in China during the Shang Dynasty (960–1279 AD). Japan and other Asian countries adopted this method of printing and advanced the craft using it in conjunction with block printing and hand applied paints. 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. Screen printing was first patented in England by Samuel Simon in 1907. It was originally used as a popular method to print expensive wall paper, printed on linen, silk, and other fine fabrics. Western screen printers developed reclusive, defensive and exclusionary business policies intended to keep secret their workshops' knowledge and techniques. 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 there are large selections of pre-sensitized and "user mixed" sensitized emulsion chemicals for creating photo-reactive stencils.
MARKET SURVEY CUM DETAILED TECHNO
ECONOMIC FEASIBILITY REPORT
covers
Introduction
Uses and Applications
Properties
Market Survey with future aspects
Present Manufacturers
Detailed Process of Manufacture
Formulations
B.I.S. Specifications
Process Flow Sheet Diagram, Plant Layout,
Cost Economics with Profitability Analysis
Capacity
Land & Building Requirements with Rates
List & Details of Plant and Machinery with their Costs
Raw Materials Details/List and Costs
Power & Water Requirements
Labour/Staff Requirements
Utilities and Overheads
Total Capital Investment
Turnover
Cost of Production
Break Even Point
Profitability
Land Man Ratio
Suppliers of Plant & Machineries and Raw Materials
Cash Flow Statement
Repayment Schedule
Interest Chart
Depreciation Chart
Projected Balance Sheet for 5 Years etc.