SCREEN PRINTINGChapter 23

Screen Printing

The process of forcing ink through a porous fabric (screen) and the open areas of a stencil to produce an image

Serigraphy, mitograph, silk screen, stencil printing, screen process

Serigraphy- fine arts Screen Printing- graphic

communications

Screen Printing

Simple Process

Complex Process

Few inexpensive tools and materials

Array of sophisticated equipment and production techniqueso Complexity

o Level of quality required in finished piece

Applications

Posters, plastic bottles, drinking glasses, soda bottles, mirrors, metal surfaces, wood, textiles, printed circuit boards, product displays, vinyl binders, etc

Versatile Process

Advantages: wide variety of substrates, easy production process, low capital expenditures, decorative finishes, resilient ink film

Disadvantages: process is limited to flat, thin substrates, slow rate of production, poor ink mileage, excessive drying times, difficult to print details and fine line images

Screen Printing Process Equipment: screen

fabric, frame, stencil, ink, squeegee, substrate

1. Porous fabric is stretched across frame

2. Stencil is adhered to fabric blocking out portions and leaving open the desired image area

3. Ink is poured onto fabric and forced through image area using a squeegee

4. Ink is deposited on substrate, producing image of cut stencil

5. Multiple prints are created by repeating the process on new substrates

Photographic Stencils

Light sensitive Exposed using a positive film image Right-reading on emulsion side Indirect: exposed off the screen

fabric Direct: exposed after a light-sensitive

emulsion has been applied to screen frame

Direct-Indirect: combination of the two stencil techniques and materials

Diazo Emulsion Used with water-based or solvent-soluble inks Applied with scoop coater to both sides of screen Substrate side of emulsion should be smooth Exposure is made with a deep-bottom vacuum frame Positive is positioned on substrate side and should be

in contact with screen emulsion Exposure to light causes areas to harden and become

insoluble in water Unexposed area will be washed away Blockout can be applied to fill in pinholes and other

uncoated areas Emulsion is removed using a reclaiming solution

Screen Preparation

Screen Exposure

One Color Printing Process

Screen Clean Up

1. What are some typical applications of screen printing?

2. What are some advantages of screen printing?

3. What are some disadvantages of screen printing?

4. Describe the basic screen printing process.

5. When using a Diazo emulsion, how should the positive be positioned?

Review Questions