Vacuum holddown device for flexographic printing plates
US4474445A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 21, 1983 |
| Grant date | Oct 2, 1984 |
| Priority date | — |
| Expiry date | Mar 21, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/3085
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A platen for supporting any one of a predetermined number of sizes of flexographic printing plates during wet development includes an interconnected orifice and a suction channel the suction channel surrounding the orifice, and an array of grooves emanating from the channel at spacings in the range from two degrees to fifteen degrees. Each groove is substantially V-shaped in cross-section and has a depth from 0.002 to 0.025 inches. The cross-sectional area of each groove being selected so that when a plate is placed over some portion of the suction channel and the grooves, a developer liquid applied to the plate, and suction applied at the orifice the flow of developer liquid from the plate through each groove is impeded by frictional effects in the grooves thereby forming a seal to permit the suction to hold the plate to the platen even though the plate does not cover the full length of all the grooves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.