Laser welding technology patent upheld

The European Patent Office has upheld TWI's Clearweld patent for laser welding of plastics

TWI anounced that the European Patent Office (EPO) upheld a key patent relating to the laser welding of plastics following oral proceedings held on September 13, 2007, in Munich, Germany.

The patent, EP 1117502, which claims the use of radiation absorbing materials to facilitate the welding process, had been initially opposed in October 2003 and revoked by the EPO in oral proceedings in February 2005. This latest ruling by the EPO successfully ends an appeal process initiated by TWI after the 2005 hearing and resulted in full validation of all claims in the patent.

Robert Skone James of Gill Jennings & Every LLP, TWI's European patent attorneys, said, "TWI's patent was opposed by many of the major players in the plastics welding field citing more than 50 documents between them. It was therefore particularly pleasing that the EPO Appeal Board maintained the patent in the face of such strong attacks, indicating the significance of the Clearweld invention."

The patent was originally granted in January 2003. Patents based upon the claims in EP 1117502 have also been granted in Australia (2002), Mexico (2003), China (2004), Japan (2005), and Brazil (2005) with patents pending in the United States, Canada, and Korea.

TWI has commercialized its laser welding technology under the Clearweld brand name through a sole license agreement with Gentex Corporation (Carbondale, PA), an advanced technology company that also manufactures proprietary radiation absorbing materials for a variety of light management applications, including laser protection and other unique light filtration products for military and commercial markets.

Gentex has also filed a number of patents related to Clearweld technology in the U.S., Mexico, Canada, Europe, Australia, China, Japan, Korea, and Russia. In addition, Gentex has entered into non-exclusive license agreements with BASF AG (Ludwigshafen, Germany) and Merck KGaA (Darmstadt, Germany) to permit them to sell their proprietary radiation absorbing materials into plastaics laser welding applications worldwide.

Information on Gentex and Clearweld can be fount at and Information on TWI can be found at

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