Complete Transfer of Liquid Drops by Modification of Nozzle Design

Promotes complete transfer of discrete drops without residuals on nozzles Enables a flexible and compact system capable of printing different samples through the same nozzle Minimizes or eliminates cleaning steps typically needed between transfers while avoiding cross-contamination, speeding printing processes Improves nozzle consistency and accuracy without increasing manufacturing cost Integrates easily with existing nozzle technologies Eliminates satellite droplets, improving quality of, e.g., inkjet printing

Biological assays/microarrays Microfluidic printing systems DNA solid pin Replicators Droplet-based discrete microfluidics Inkjet printing systems

The novel method enables complete transfers of liquid droplets from a printhead to the printing surface. The effective energy at the nozzle circumference holding back the droplets is reduced, and adhesion between the liquid and print nozzle is lowered. Printhead pull-back is thereby minimized, ensuring no printhead residuals. Accordingly, the printed droplet volume consistently and accurately matches the intended droplet volume. Further, cleaning steps are minimized, which speeds printing processes. The treatment is permanent and does not require any extra step, unlike coating of the nozzle.

Patent Number: US7458661B2
Application Number: US2006275668A
Inventor: Kim, Chang-Jin | Yi, Uichong Brandon
Priority Date: 25 Jan 2005
Priority Number: US7458661B2
Application Date: 23 Jan 2006
Publication Date: 2 Dec 2008
IPC Current: B41J000214 | B41J000216
US Class: 347047 | 347045 | 347048
Assignee Applicant: The Regents of the University of California
Title: Method and apparatus for promoting the complete transfer of liquid drops from a nozzle
Usefulness: Method and apparatus for promoting the complete transfer of liquid drops from a nozzle
Summary: Used for transferring liquid droplet (claimed) from an orifice/nozzle.
Novelty: Print head device for transferring liquid droplet, has nozzle with orifice having inner circumferential surface, where fluid is transferred to another surface by contacting bulging droplet in nozzle with printing surface

Electronics

3C/Gadgets

7458661

State of Development

The device has been fabricated, tested, and verified.

Background

Droplet printing precision is important for DNA/protein microarrays. Droplet variations cause detection errors. Inkjet-based and pin-based printing can produce inconsistent droplet volume. When transferred through a nozzle, liquid droplets tend to leave residuals on the printhead after printing. Residuals cause inconsistent printed droplets, and increase the need for cleaning to avoid cross contamination between different sample liquids.

Additional Technologies by these Inventors

• Micropumping of Liquids by Directional Growth and Selective Venting of Bubbles
• High-speed Switching of Droplet by Electric Meniscus Actuation
• Selective Surface Coating and/or Treatment of Printing Pins
• On-chip, Real-time Feedback Control for Electrical Manipulation of Droplets
• Localized Droplet Heating with Surface Electrodes in Microfluidic Chips
• No-Assembly Devices for Microfluidics Inside a Cavity
• Methods of Restoring and Maintaining Gas Film on Superhydrophobic Surfaces while Underwater
• Membraneless Fuel Cell with Self-Pumped Fuel and Oxidant
• Microstructured Cathode for Self-Regulated Oxygen Generation and Consumption
• Liquid-Repellent Surfaces Made of Any Materials
• A Low-Profile Flow Shear Sensing Unit
• Method for Commercial Production of Super-Hydrophobic Materials
• Method of Fluid Manipulation By Electrodewetting

Tech ID/UC Case

20151/2005-409-0

Related Cases

2005-409-0

USA

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