Apparatus and method for measuring percentage solids in liquid developer material

In a printing system with a liquid developer material application member for receiving liquid developer material containing solids for application of the liquid developer material to a selected surface, the liquid developer material, when disposed on the developer application member as a film being characterized by a first value varying as a function of developed mass per unit area (DMA) and a second value varying as a function of film thickness, the liquid developer application member being characterized by a capacitance when liquid developer material is disposed thereon and the capacitance being represented by a signal, a system for measuring a percentage of the solids in the liquid developer material, comprising:

• a first sensing system for determining a magnitude corresponding with the first value, wherein said first sensing system determines the magnitude corresponding with the first value by specific reference to the capacitance;
• a second sensing system for determining a magnitude corresponding with the second value;
• a controller, responsive to said first and second sensing systems, for determining the percentage of the solids in the liquid developer material with the determined first and second values;
• and
• wherein the signal is normalized to accommodate for nonuniformity in the liquid developer material application member.

In a printing system with a liquid developer material application member for receiving liquid developer material containing solids for application of the liquid developer material to a selected surface, the liquid developer material, when disposed on the developer application member as a film being characterized by a first value varying as a function of developed mass per unit area (DMA) and a second value varying as a function of film thickness, a method for measuring a percentage of the solids in the liquid developer material, comprising:

• a) determining a first magnitude corresponding with the first value;
• b) determining a second magnitude corresponding with the second value;
• and
• c) receiving the first and second magnitudes, with a controller, for determining the percentage of the solids in the liquid developer material, wherein said c) includes determining the percentage of solids in the liquid developer material with the following relationship:
• Percentage Solids=DMA/(Film Thickness.times.Density of Liquid Developer Material).
• 8.

In a printing system with a liquid developer material application member for receiving liquid developer material containing solids for application of the liquid developer material to a selected surface, the liquid developer material, when disposed on the developer application member as a film being characterized by a first value varying as a function of developed mass per unit area (DMA) and a second value varying as a function of film thickness, the liquid developer application member being characterized by a capacitance when liquid developer material is disposed thereon and the capacitance being represented by a signal, a method for measuring a percentage of the solids in the liquid developer material, comprising:

• a) determining a first magnitude corresponding with the first value;
• b) determining a second magnitude corresponding with the second value, wherein said a) includes determining the first magnitude by specific reference to the capacitance;
• c) receiving the first and second magnitudes, with a controller, for determining the percentage of the solids in the liquid developer material;
• and
• d) normalizing the signal to accommodate for nonuniformity in the liquid developer material application member.