Screen Printing on Aluminum and Stainless Steel
The screen printing process is a standard process in the decoration of metal and plastic nameplates, labels and emblems. It is typically used for graphics or background color application. The colors are custom matched in opaque, transparent or metallic effects. Screen printing is also used to add selective gloss levels or textures to nameplates. This article focuses on the screen printing process on metal substrates.
Definition: Screen printing, also known as screening or serigraphy, is a print making technique that traditionally creates a sharp-edged, single-color image. A stencil is created by use of a photosensitive emulsion and a mesh fabric. Ink is forced through the screen with a squeegee.
Alternative names: screening, screen printing, printing
close up of a screen showing the mesh fabric and stencil image
screening machine showing image being printed
Screen Print Advantages
•colors more opaque (typically only one hit or application of color is required)
•top coat isn't always required (part performance specifications determine whether a topcoat is needed)
•colors can be combined with textures
•color and gloss can be combined into one operation
Screen Printing on Metal Options
•color
opaque or transparent
metallics
•textures
clear or colored
high or low gloss
soft-touch
•processes which can be combined with silk screening
mechanical finishes
lensing
diamond cutting
Considerations
•part geometry and performance specifications help to determine which decorative process is appropriate for each application
•typically screen printing does not require multiple impressions to achieve a color
•a base color may need to be applied underneath a color (required for light or bright colors)
•each hit must be cured before applying next color or process
•there is a one time artwork preparation charge for each color
Alternative Processes to Screen Printing
•solid colors: coating, lithography
•spot color: lithography
Technical Information
•resists for mechanical finishes and chemical etching are screened
•cannot obtain the ultra fine detail available in lithography (minimum screening stroke width: .007" pos. print, .007" neg. print)
•chokes and flares are required when applying multiple colors next to each other
•graphics are generally choked or flared .010" for screening
•chemical etch requires an additional resist on the back of sheets
•lithography is a preferred process for critical registration of graphics
Additional questions and answers focusing on nameplate, label and badge design and manufacturing can be found on our Nameplate FAQ page.
