Browse Prior Art Database

Cascading Image Developer Disclosure Number: IPCOM000083863D
Original Publication Date: 1975-Aug-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 3 page(s) / 40K

Publishing Venue


Related People

Ludden, RC: AUTHOR


The described system provides an economical method for developing exposed images on printed-circuit panels.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Cascading Image Developer

The described system provides an economical method for developing exposed images on printed-circuit panels.

In operation, clean developing solvent enters the developing tank 1 through feed pipe 2. Filters, flow control valves, etc., may be used directly ahead of this. The solution immediately encounters the first baffle plate 3, which allows filling of cell 4 through the standoff space 5 of the baffle 3. Assuming the system has been previously filled, excess fluid passes over weir plate 6 into the second cell
7. The process is repeated through the remaining cells 8 and 9, although the exact number of cells must be determined by the intended application. At the last cell, fluid is discharged through exit port 10 to be repurified.

Developing action is accomplished by heating each cell to a vigorous boiling. Heating elements 11 produce bubbling 12 which causes a turbulent flow against workpiece 13. To insure a homogenous bubbling pattern alone the workpiece, the convection currents are guided by a stream director plate 14 in each cell, which returns the fluid to the heating element area.

The weir plates 6 are curled along their top edges to promote transport of floating particulate matter out of the working area of the cells. From time-to-time, these narrow chambers between weir 6 and baffle plates 3 can be skimmed through valved ports 15.

Workpieces are developed by consecutive immersion in cells 9, 8, 7, and 4, working upstream.

The redirection of fluid by baffle plates 3 through the cells, assures that fluid from the previous or upstream cell becomes more of an integral part of the fluid makeup in the cell; nor just passing along the top of the solution and over the next weir, a...