| 摘要 |
A stencil manufacturing and printing process reduces printed image distortion by matching screen deflection in the photostencil preparation phase with stencil deflection in the printing phase. The usual squeegee is replaced by atmospheric pressure and screen/stencil deflection is induced by producing a vacuum in a gasketed airtight chamber under the screen through a specially constructed air distribution frame. Compressed air can be introduced in the chamber through the same frame to rapidly release the stencil from the substrate when the printing is completed. A control unit incorporating a pressure sensor facilitates control of the printing process. Correlation of screen tension constant and frame off-contact distance with chamber pressure readings provides a precise measure of screen area of contact. The frame may have a 2-piece construction with the stencil/screen supported by a removable insert and the air distribution and pressure level sensing functions afforded by a master frame into which the insert fits.
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