U.S. Philips Corporation

Antonius W De Laat

Hermannus F Schoo

The invention relates to a stable aqueous dispersion of particles which can be flocculated by increasing the temperature to a value above the transition temperature. The invention is characterized in that the dispersion comprises a polymer selected from the group consisting of polyvinyl methyl ether and a block copolymer of polyvinyl methyl ether and a polyvinyl ether, the ether group bonded to the main chain via the oxygen atom being adsorbed onto the surface of the particles. The invention also relates to a block polymer of the above-mentioned type and to a method of manufacturing such a block copolymer. The invention enables very fine powders of ceramic particles having a very high homogeneity to be obtained.

Aqueous dispersion of particles

A method of manufacturing a metal matrix in which a supporting plate bearing a photo-resist layer is irradiated patternwise, the irradiated parts are developed and thereby removed, the obtained master disc is provided with a metal peel, which subsequently is removed, whereby after removal of the patternwise irradiated parts of the photoresist layer, the remaining parts are irradiated. The invention also relates to a new intermediate product which comprises a supporting layer, a photoresist layer having an information track and an electrically conductive layer on the photoresist layer, the photoresist layer being a fully irradiated layer.

Method of manufacturing a metal matrix and an intermediate product

A method of manufacturing a metal mother matrix in which a master disk, which is a supporting disk, carrying on one side a layer of a positive photoresist in which an information track is provided, is provided with a metal peel, first by electroless deposition and then by electrodeposition, the metal peel is separated from the master disk, the remainders of the photoresist present on the father matrix thus obtained are dissolved and a metal copy, which is a mother matrix, is manufactured by electrodeposition from the father matrix, characterized in that the photoresist is made electrically conductive by means of exposure to light.

Growing community of inventors

Eindhoven, Netherlands

Antonius W De Laat