Print head for use in a ballistic aerosol marking apparatus

• US 6,116,718 A
• Filed: 09/30/1998
• Issued: 09/12/2000
• Est. Priority Date: 09/30/1998
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Lean, Meng H., Floyd, Philip D., Noolandi, Jaan, Peeters, Eric, Volkel, Armin R., Apte, Raj B.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): Stephens, Juanita
• Application Number:
  US09/163,904
• Time in Patent Office: 713 Days
• Field of Search: 347/21, 347/46, 347/43, 347/20, 347/54, 347/65, 347/67, 239/422
• US Class Current: 347/21
• CPC Class Codes: B41J 2/01 Ink jet
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14008 Structure of acoustic ink jet print heads
• CPC Class Codes: B41J 2202/02 Air-assisted ejection

Abstract

A print head is disclosed for use in a marking apparatus in which a propellant stream is passed through a channel and directed toward a substrate. Marking material, such as ink, toner, etc., is controllably introduced into the propellant stream and imparted with sufficient kinetic energy thereby to be made incident upon a substrate. A multiplicity of channels for directing the propellant and marking material allow for high throughput, high resolution marking. Multiple marking materials may be introduced into the channel and mixed therein prior to being made incident on the substrate, or mixed or superimposed on the substrate without registration.

Claims

1. A print head, comprising:

a substrate having formed therein first and second channels, each said channel having a propellant receiving region, a marking material receiving region, and an exit orifice, each said exit orifice having a width greater than zero micrometers but not exceeding 250 micrometers;

a material layer disposed over said substrate, said material layer being provided with first and second marking material ports, said first marking material port in communication with the marking material receiving region of said first channel, said second marking material port in communication with the marking material receiving region of said second channel, said material layer further provided with first and second propellant ports, said first propellant port in communication with the propellant receiving region of said first channel, said second propellant port in communication with the propellant receiving region of said second channel;

such that propellant provided to said propellant receiving region of each said channel may be caused to form a propellant stream travelling through each said channel to and through said exit orifice of each said channel, and marking material provided to each said marking material receiving region may be caused to enter each said propellant stream and imparted with sufficient energy thereby to travel to and through each said exit orifice.

2. The print head of claim 1, wherein said first and second propellant ports are formed in said material layer.

3. The print head of claim 1, wherein each said channel further comprises a converging region and a diverging region, said converging region and said diverging region formed between said propellant receiving region and said marking material receiving region of said channel, wherein for each said channel said propellant stream may enter said converging region at a first velocity and first pressure and flow into said diverging region, and further wherein said propellant may exit said diverging region at a second velocity and a second pressure, said first pressure greater than said second pressure and said first velocity less than said second velocity.

4. The print head of claim 1, further comprising first and second electrodes, said first electrode disposed in said marking material receiving region of said first channel proximate said first port, and said second electrode disposed in said marking material receiving region of said second channel proximate said second port.

5. The print head of claim 1, wherein each said first and second channel are formed to include a cross sectional profile which is selected from the group comprising:

square, rectangular, oval, semi-oval, circular, semi-circular, and triangular.

6. The print head of claim 1, wherein when marking material introduced into said propellant stream in said first channel exits said exit orifice of said first channel a first marking material stream is produced, and wherein when marking material introduced into said propellant stream in said second channel exits said exit orifice of said second channel a second marking material stream is produced, each said marking material stream having a width which does not deviate by more than 10 percent from the width of the exit orifice from which it exits for a distance, in a direction of travel of the marking material stream, of at least 4 times the width of the exit orifice it exits.

7. A print head for use in a ballistic aerosol printer, comprising:

a substrate;

a first layer, formed over said substrate, in which at least two adjacent channels are formed, each said channel extending from a proximal end to a distal end at which is located an exit orifice, each said exit orifice having a width less than 250 micrometers;

a second layer, formed over said first layer, substantially covering said channels, said second layer having formed therein at least one port in communication with each said channel;

whereby a propellant may be introduced at said proximate end into said channel and travel within said channel toward said distal end, and further whereby a marking material may be introduced through said at least one port into said channel and into said propellant to be carried thereby out of said exit orifice.

8. The print head of claim 7, wherein said first and second layers are formed of a photosensitive material.

9. The print head of claim 8, wherein said first layer is formed of a spin-on photosensitive material and said second layer is formed of a dry-film photosensitive material, and further where said second layer is laminated onto said first layer.

10. The print head of claim 7, further comprising an insulating layer formed over said substrate between said substrate and said first layer.

11. The print head of claim 7, wherein each said channel includes a diverging region and a converging region, and wherein said propellant may be introduced into said converging region at a first velocity and first pressure and flow into said diverging region, and further wherein said propellant exits said diverging region at a second velocity and a second pressure, said first pressure greater than said second pressure and said first velocity less than said second velocity.

12. The print head of claim 7, wherein said second layer has a first side facing said channel and a second side facing away from said channel, and further wherein each port has associated therewith a pair of electrodes, a first electrode of said pair located proximate said first side and a second electrode of said pair located proximate said second side.

13. The print head of claim 12, wherein said first electrode is located within said channel.

14. The print head of claim 13, wherein said channel has a lower surface which is a surface on which said first layer is formed, and further wherein said first electrode is located on said lower surface.

15. The print head of claim 12, wherein each pair of first and second electrodes are independently addressable.

16. The print head of claim 12, wherein said each said port is generally cylindrical, and each said first and second electrodes are generally annular, and further wherein each said first and second electrodes are positioned concentric with said port with which they are associated.

17. The print head of claim 7, further comprising a plurality of propellant ports formed in said substrate, each said propellant port in communication with one of said channels at said proximal end thereof.

18. The print head of claim 7, further comprising a plurality of propellant ports formed in said first layer, each said propellant port in communication with one of said channels at said proximal end thereof.

19. The print head of claim 7, further comprising a third layer, disposed between said first layer and said second layer, said third layer having a plurality of third layer channels formed therein such that no third layer channel directly overlies, nor is in communication with a channel in said first layer, and further wherein said second layer has formed therein at least one third layer port, such that each said third layer channel has a port in communication therewith.

20. The print head of claim 7, wherein for each channel, when marking material introduced into a propellant stream in said channel exits said exit orifice of said channel a marking material stream is produced, said marking material stream having a width which does not deviate by more than 10 percent from the width of the exit orifice from which it exits for a distance, in a direction of travel of the marking material stream, of at least 4 times the width of the exit orifice it exits.