Microfluidic printing with controlled density

• US 5,982,401 A
• Filed: 10/03/1997
• Issued: 11/09/1999
• Est. Priority Date: 10/03/1997
• Status: Expired due to Fees

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Wen, Xin, Fassler, Werner, Deboer, Charles D.
• Primary Examiner(s): Le, N.
• Assistant Examiner(s): Nguyen, Lamson D.
• Application Number:
  US08/943,105
• Time in Patent Office: 767 Days
• Field of Search: 346/140.1, 347/6, 347/7
• US Class Current: 346/140.1
• CPC Class Codes: B41J 2/005 characterised by bringing liquid or particles selectively into contact with a printing material printing by selective application of impact or pressure on a printing or impression-transfer material B41J2/22
• CPC Class Codes: B41J 2002/0052 Control methods or devices for non ink jet heads
• CPC Class Codes: B41J 2202/05 Heads having a valve

Abstract

A microfluidic printing system for delivering ink to a receive including at least one ink reservoir, a structure defining a plurality of chambers arranged so that the chambers from an array with each chamber being arranged to form an ink pixel for delivery to the receiver, and a plurality of microchannels connecting the reservoir to the chambers. The printing system further includes a plurality of microfluidic pumps each being associated with a single microchannel for supplying ink from an ink reservoir through a microchannel for delivery to a particular chamber. The system is responsive to the flow of the ink through the chambers to determine the amount of ink being delivered to a receiver through the chambers, and further controls the microfluidic pumps to prevent the further flow of ink to the receiver.

Claims

1. A microfluidic printing system for delivering ink to a receiver comprising:

a) at least one ink reservoir,

b) a structure defining a plurality of chambers arranged so tha the chambers form an array with each chamber being arranged to form an ink pixel for delivery to the receiver;

c) a plurality of microchannels connecting said at least ink reservoir to the chambers;

d) a plurality of microfluidic pumps each being associated with a single microchannel of said plurality of microchannels for supplying ink from said at least one ink reservoir though a microchannel of said plurality of microchannels for delivery to a particular chamber of said plurality of chambers, each pump including a least two spaced apart electrodes and means coupled to the electrodes for producing an electrical field in response to an input voltage that act upon the ink to control or prevent an ink flow;

e) means responsive to the flow of ink for providing a flow measuring signal to the electrodes and means responsive to variations in a signal parameter of the applied signal across the electrodes for measuring the flow of the ink through the chambers to determine a correct around of ink being delivery to the receiver through the chambers; and

f) means couple to the ink flow responsive means for controlling the microfluidic pumps to prevent a further flow of ink the receiver.

2. A microfluidic printing system for delivering ink having conductor material to a receiver comprising:

a) at least one ink reservoir;

b) a structure defining a plurality chambers arranged so that the chambers form an array with each chamber being arranged to form a conductive ink pixel for delivery to the receiver;

c) a plurality of microchannels connecting said at least one ink reservoir to the chambers;

d) a plurality of microfluidic pumps each being associated with a single microchannel of said plurality of microchannels for supplying conductive ink from said at least one ink reservoir through a microchannel of said plurality of microchannels for delivery to a particular chamber of said plurality of chambers, each pump including at least two spaced apart electrodes which produce an electric field in response to an input voltage that act upon the conductive ink to control or prevent an ink flow;

e) means for providing a high frequency flow measuring signal to the electrodes and means responsive to variations in the signal applied across the electrodes for measuring the flow of the conductive ink through the chambers to determine a correct amount of conductive ink being, delivered to the receiver through the chambers; and

f) flow control means including a source of DC voltage and means f or applying the DC voltage applied across the electrodes of each microfluidic pump of plurality of microfluidic pumps in a first direction for causing the ink to flow through the chambers to the receiver and, in a second direction, for preventing the ink flow to the receiver;

such flow control means being coupled to the ink flow responsive means for causing the DC voltage to be applied in the second direction to prevent a further flow of ink to the receiver when the correct amount of ink is delivered to the receiver.