Henkel Ag & Company, Kgaa

Louis Patrick Rector

Donald Robb Vonk

Qizhuo Zhuo

Pukun Zhu

Shashi K Gupta

Shashi Gupta

The tendency of a bare metal surface to oxidize (e.g., flash-rust) may be alleviated by contacting the bare metal surface with an aqueous mixture of at least one preformed reaction product obtained by reaction of at least one catechol compound, such as dopamine or a salt thereof, with at least one co-reactant compound functionalized with one or more functional groups reactive with the at least one catechol compound, such as (meth)acryl, primary amino, secondary amino, thiol and/or hydroxyl groups, with polyethyleneimine being an example of a suitable co-reactant compound. Such a rinsing procedure does not interfere with subsequent conversion coating of the metal surface.

Use of preformed reaction products of catechol compounds and functionalized co-reactant compounds to reduce oxidation of bare metal surfaces

Provided herein are sinterable films and pastes as conductive die attach materials having advantageous properties for use in die semiconductor packages. Also provided are formulations useful for the preparation of such films and pastes, as well as methods for making such formulations. In additional aspects of the present invention, there are provided conductive networks prepared from compositions according to the present invention. In certain aspects, the invention relates to articles comprising such sintering films and pastes adhered to a suitable substrate therefor.

Sinterable films and pastes and methods for use thereof

The corrosion resistance of conversion-coated metal substrate surfaces is further enhanced by treating such surfaces with aqueous mixtures of preformed reaction products obtained by reacting catechol compounds, such as dopamine or a dopamine salt, and functionalized co-reactant compounds, such as a polyethyleneimine.

Treatment of conversion-coated metal substrates with preformed reaction products of catechol compounds and functionalized co-reactant compounds

An aqueous, acidic, anti-corrosion conversion coating composition (in particular, an aqueous, acidic Group IV metal-containing anti-corrosion conversion coating composition) for metal substrates comprising as an additive a catechol compound and/or the reaction products of at least one catechol compound and at least one co-reactant compound having one or more functional groups reactive with the at least one catechol compound, desirably the reaction product of a catechol and an polyamine (e.g., a polyethyleneimine), that enhances the anti-corrosion effects of the conversion coating composition; methods of making and applying the conversion coating compositions and coated metal substrates. The catechol-containing conversion coating composition can be applied to metal substrate surfaces at temperatures as low as below 40&#xb0; C. and with exposure times of 5 minutes or less. The catechol compound or reaction product thereof can become incorporated into the conversion coating formed on the metal substrate.

Growing community of inventors

Rochester Hills, MI, United States of America

Louis Patrick Rector