Nozzle placement in monolithic drop-on-demand print heads
AssigneeEastman Kodak Company
InventorKia Silverbrook
Life of this patent
Estimating the term…
Abstract
An improved print head construction for maintaining wafer strength along the line of nozzles at approximately 50% of the normal wafer strength. This is achieved by dividing each row of nozzles into segments, and by displacing some of those segments (preferably every alternate segment) in the print direction. Displacement of the segment of nozzles is in the print direction so that the nozzles can still print the same pixels to the recording medium, simply by altering the time that the nozzles are provided with the particular information to be printed. The distance that the displaced segments are displaced is preferably slightly more than the width of the slot (or ink channel) in which the nozzles in the appropriate segment are formed.
Claims18
A drop on demand printing head comprising:
- substrate having front and back surfaces;
- a plurality of nozzles formed as holes communicating between the back surface of said substrate and the front surface of said substrate, said nozzles being formed in one or more row regions which are generally perpendicular to a print direction, each of said regions being divided into a plurality of multi-nozzle groups at least some of said groups within the regions being displaced in the print direction from other of said groups in the same row region;
- a body of ink associated with said nozzles;
- a pressurizing device adapted to subject ink in said body of ink to a pressure of at least 2% above ambient pressure, at least during drop selection and separation to form a meniscus with an air/ink interface;
- drop selection apparatus operable upon the air/ink interface to select predetermined nozzles and to generate a difference in meniscus position between ink in selected and non-selected nozzles;
- and
- drop separation apparatus adapted to cause ink from selected nozzles to separate as drops from the body of ink, while allowing ink to be retained in non-selected nozzles.
A drop on demand printing head comprising:
- a substrate having front and back surfaces;
- a plurality of nozzles formed as holes communicating between the back surface of said substrate and the front surface of said substrate, said nozzles being formed in one or more row regions which are generally perpendicular to a print direction, each of said regions being divided into a plurality of multi-nozzle groups at least some of said groups within the regions being displaced in the print direction from other of said groups in the same row region;
- a body of ink associated with said nozzles said body of ink forming a meniscus with an air/ink interface at each nozzle;
- drop selection apparatus operable upon the air/ink interface to select predetermined nozzles and to generate a difference in meniscus position between ink in selected and non-selected nozzles;
- and
- drop separation apparatus adapted to cause ink from selected nozzles to separate as drops from the body of ink, while allowing ink to be retained in non-selected nozzles, said drop selection apparatus being capable of producing said difference in meniscus position in the absence of said drop separation apparatus.
A drop on demand printing head comprising:
- a substrate having front and back surfaces;
- a plurality of nozzles formed as holes communicating between the back surface of said substrate and the front surface of said substrate, said nozzles being formed in one or more row regions which are generally perpendicular to a print direction, each of said regions being divided into a plurality of multi-nozzle groups at least some of said groups within the regions being displaced in the print direction from other of said groups in the same row region;
- a body of ink associated with said nozzles, said body of ink forming a meniscus with an air/ink interface at each nozzle and said ink exhibiting a surface tension decrease of at least 10 mN/m over a 30.degree. C. temperature range;
- drop selection apparatus operable upon the air/ink interface to select predetermined nozzles and to generate a difference in meniscus position between ink in selected and non-selected nozzles;
- and
- drop separation apparatus adapted to cause ink from selected nozzles to separate as drops from the body of ink, while allowing ink to be retained in non-selected nozzles.
Dependencies are inferred from the claim text.