Inkjet printhead with heaters suspended by sloped sections of less resistance

• US 7,950,779 B2
• Filed: 11/15/2009
• Issued: 05/31/2011
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Do; An H
• Application Number:
  US12/618,750
• Publication Number:
  US 20100060698A1
• Time in Patent Office: 562 Days
• Field of Search: 347/54, 347/56, 347/62, 347/65
• US Class Current: 347/62
• CPC Class Codes: B41J 2/1412 Shape
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1601 Production of bubble jet print heads B41J2/1606, B41J2/162 take precedence
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1626 etching
• CPC Class Codes: B41J 2/1628 dry etching
• CPC Class Codes: B41J 2/1629 wet etching
• CPC Class Codes: B41J 2/1631 photolithography
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/1635 dividing the wafer into individual chips
• CPC Class Codes: B41J 2/1637 molding
• CPC Class Codes: B41J 2/1639 sacrificial molding
• CPC Class Codes: B41J 2/1642 thin film formation by CVD [chemical vapor deposition]
• CPC Class Codes: B41J 2/1643 thin film formation by plating
• CPC Class Codes: B41J 2/1645 thin film formation by spincoating
• CPC Class Codes: B41J 2/1646 thin film formation by sputtering
• CPC Class Codes: B41J 2/1648 Production of print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/16585 for paper-width or non-reciprocating print heads
• CPC Class Codes: B41J 2/17503 Ink cartridges
• CPC Class Codes: B41J 2/17513 Inner structure
• CPC Class Codes: B41J 2/17596 : Ink pumps, ink valves
• CPC Class Codes: B41J 2002/041 : Electromagnetic transducer
• CPC Class Codes: B41J 2002/14346 : Ejection by pressure produced by thermal deformation of ink chamber, e.g. buckling
• CPC Class Codes: B41J 2002/14435 : Moving nozzle made of thermal bend detached actuator
• CPC Class Codes: B41J 2202/21 : Line printing
• CPC Class Codes: B82Y 30/00 : Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G06F 1/1626 : with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 21/79 : in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 21/86 : Secure or tamper-resistant housings
• CPC Class Codes: G06F 2221/2129 : Authenticate client device independently of the user
• CPC Class Codes: G06K 1/121 : by printing code marks applying code marks to labels B65C9/46; marking or coding completed packages B65B61/26
• CPC Class Codes: G06K 19/06037 : multi-dimensional coding
• CPC Class Codes: G06K 7/14 : using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1417 : 2D bar codes
• CPC Class Codes: G11C 11/56 : using storage elements with more than two stable states represented by steps, e.g. of voltage, current, phase, frequency
• CPC Class Codes: H04N 1/2154 : the still video camera incorporating a hardcopy reproducing device, e.g. a printer
• CPC Class Codes: H04N 2101/00 : Still video cameras
• CPC Class Codes: H04N 23/00 : Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 5/2628 : Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation
• CPC Class Codes: Y10T 29/49401 : Fluid pattern dispersing device making, e.g., ink jet

Abstract

An inkjet printhead that has a pair of electrodes, a heater having contacts abutting the pair of electrodes, a heater element for generating a vapor bubble in a quantity of ink and sloped side portions extending between the heater element and the contacts and, a nozzle spaced from the heater such that ink is ejected through the nozzle in response to the generation of a vapor bubble. The heater element has higher electrical resistance than the contacts and the sloped side portions.

Claims

1. An inkjet printhead comprising:

a pair of electrodes;

a heater having contacts abutting the pair of electrodes, a heater element for generating a vapour bubble in a quantity of ink and sloped side portions extending between the heater element and the contacts; and

,

a nozzle spaced from the heater such that ink is ejected through the nozzle in response to the generation of a vapour bubble;

wherein,

the heater element has higher electrical resistance than the contacts and the sloped side portions.

2. The inkjet printhead according to claim 1 wherein the heater comprises TiAlN.

3. The inkjet printhead according to claim 1 wherein the heater element is ring shaped.

4. The inkjet printhead according to claim 1 configured to print on a page and to be a pagewidth printhead.

5. The inkjet printhead according to claim 1 wherein the heater element is coated with a passivating material.

6. The inkjet printhead according to claim 1 wherein the heater element is configured such that an actuation energy of less than 500 nanojoules (nJ) is required to be applied to that heater element to heat that heater element sufficiently to form said vapour bubble to cause the ejection of said drop.

7. The inkjet printhead according to claim 1 configured to receive a supply of the ink at an ambient temperature, wherein each heater element is configured such that the energy required to be applied thereto to heat said part to cause the ejection of said drop is less than the energy required to heat a volume of said ink equal to the volume of the said drop, from a temperature equal to said ambient temperature to said boiling point.

8. The inkjet printhead according to claim 1 comprising a substrate having a substrate surface, wherein the areal density of the nozzles relative to the substrate surface exceeds 10,000 nozzles per square cm of substrate surface.

9. The inkjet printhead according to claim 1 wherein the heater element has two opposite sides and is configured such that said vapour bubble formed by that heater element is formed at both of said sides of that heater element.

10. The inkjet printhead according to claim 1 wherein the vapour bubble is collapsible and has a point of collapse, and the heater element is configured such that the point of collapse is spaced from the heater element.

11. The inkjet printhead according to claim 1 comprising a structure that is formed by chemical vapor deposition (CVD), the nozzles being incorporated on the structure.

12. The inkjet printhead according to claim 11 wherein the structure is less than 10 microns thick, the nozzles being incorporated on the structure.

13. A printhead integrated circuit according to claim 1 wherein the heater element is formed of solid material more than 90% of which, by atomic proportion, is constituted by at least one periodic element having an atomic number below 50.

14. The inkjet printhead according to claim 1 wherein the heater element includes solid material and is configured for a mass of less than 10 nanograms of the solid material of that heater element to be heated to a temperature above said boiling point thereby to heat said part of the ink to a temperature above said boiling point to cause the ejection of said drop.

15. The inkjet printhead according to claim 1 wherein the heater element is substantially covered by a conformal protective coating, the coating of each heater element having been applied substantially to all sides of the heater element simultaneously such that the coating is seamless.