Development of Ink-Jet Printable Highly-Concentrated Polyimide Ink

  Chisso Corporation (Headquarters: Chiyoda-ku, Tokyo, President: Shunichi Okada) has developed an ink-jet printable and highly concentrated polyimide ink that can get a thicker film.

 

  Dielectric materials are essential for a wide variety of electronics products and are used for insulation of metal wiring in integrated circuits, etc. In recent years, miniaturization of the wiring and multi-layering are far proceeding in the area of electronic components, which causes requirements of patterning into complicated and fine shapes.

 

  Photolithographic method that involves an exposure and a development process is widely utilized as the technology, which can form fine patterns of wirings and insulation layers. But this method has very long and tangled processes and it needs large-size equipments. Moreover, raw materials are also wasted in the process of the development. As a result, cost-reduction and environmental measures have been strongly required.

 

  The dielectric ink, which Chisso developed at this time, is a polyimide system dielectric material that can be patterned by ink-jet printing. Comparing with the photolithographic method, it has some advantages as follows;

 

  (1) Since ink-jet is "drop-on-demand" printing method, it excels in terms of both the cost and the environmental load.

  (2) Able to save the equipment investment and build up an easier production process.

  (3) Due to the polyimide system, the ink has an advantage in electrical insulating properties, and is excellent in heat and chemical resistance.

  (4) "Higher solid content (25 to 60wt.%)" realizes thicker film.

  (5) "NMP(N-methyl-2-pyrrolidone)-Free"(NMP: popular solvent for polyimides) brings applicability to ink-jet printing device which might be corroded by the solvent .

 

  Particularly, (4) and (5) are unique selling points as ink-jet printable polyimide dielectric ink.

 

  The dielectric ink will be exhibited both in "IMID Exhibition 2007" held at Daegu, Korea from August 29^th and in "FPD International 2007" held at Yokohama, Japan from October 24^th.