Printers' National Environmental Assistance Center
banner

Home

Search

Virtual Printing Plants

Virtual Printing Plants Home

Virtual Flexo Plant

Virtual Litho Plant

Virtual Digital Plant - Coming Soon

Virtual Gravure Plant - Coming Soon

Vendors & Suppliers

Fact Sheets & Case Studies

Listservs & Archives

Contacts & Links

Programs

Compliance Info

Print Process Descriptions

Training

Training Home

Videoconferences

All

Lithography

Flexography

Screen Printing

Gravure

Other Sources of Printing Related Environmental Training

Safety

Calendars of Events

Ask PNEAC

Feedback

What is PNEAC?

Print Process Descriptions: Printing Industry Overview: Screen Printing

Reclaiming screens involves 2 to 3 steps.

1. Remove the ink:

Any and all excess ink in the screen should be "carded off" for reuse on another job. The screen must then be washed to remove any remaining ink because the ink will interfere with the process of removing the stencil. Screen cleaning solvents are a source of VOC emissions.

2. Emulsion removal:

The stencil or emulsion is removed by spraying the screen with a solution of water and emulsion remover chemicals which is comprised mainly of sodium metaperiodate. Then rinsing the solution away with fresh water.

The emulsion remover solution should not be permitted to dry on the surface of the screen. The emulsion and remover will become virtually impossible to remove if allowed to dry. Repeated rinsing will result in excess waste water that must be disposed of as a regulated waste and will not significantly improve the situation.

3. Haze or ghost image removal:

Finally, if any haze or "ghost image" remains, a haze remover must be applied. Some haze remover products are caustic and can damage or weaken the screen. Haze removers make screens brittle and tear easily, therefore only small amounts should be used. Ghost image is a shadow of the original image that remains on the screen caused by ink or stencil caught in the threads of the screen.

©PNEAC | Disclaimer / Copyright Info | Email the PNEAC Webmaster

Home | Search | What is PNEAC? | Contact Us

VPP | Vendors & Suppliers | Fact Sheets & Case Studies | Listservs & Archives | National Contacts & Links | Programs | Compliance Information
Print Processes & Descriptions | Training | Calendar of Events | Feedback