US 6,706,394 B2 · Method and apparatus for manufacture of magnetizable microparticles

Abstract

The subject invention related to methods and apparatuses for the manufacture of magnetizable carrier particles. In addition the subject invention pertains to particles having one or more of a variety of particle configurations and/or functional features. These geometric particle configurations and/or functional features such as delivering or removing a pay load can be tailored to achieve one or more desired missions. The subject invention also pertains to a method and apparatus for the delivery of particles to target materials, in order to accomplish one or more of a variety of missions. In a specific embodiment of the subject invention, acicular and other particles with a lengthwise dimension that are substantially uniform and homogenous in their geometry are manufactured and provided with magnetizations. In this way, predictable mechanical force responsivity can be achieved when these particles are subjected to an external magnetic field gradient.

Claims39

Dependent claims

A method of making magnetizable microparticles, comprising the steps of:

providing an electrically conductive base medium;
depositing a layer of photoresist on said base medium to yield a composite comprising said base medium and a surface layer of photoresist;
exposing portions of said surface layer to an ultraviolet light source;
etching said surface layer with photoresist solvent, thereby producing microcavities of a predominantly lengthwise dimension in said surface layer;
contacting said surface layer with an electrolytic bath, said bath being in a container and comprising metallic salts or alkaline combined ions, such that upon the application of voltage to said bath, said composite acts as a cathode and said container acts as an anode;
applying voltage to said bath, whereby metal ions in said bath move toward said surface layer and are therein deposited in said microcavities wherein they form magnetizable microparticles;
freeing said magnetizable microparticles from said surface layer;
and
collecting said microparticles.

6 more elements

Dependencies are inferred from the claim text.

Method and apparatus for manufacture of magnetizable microparticles

Life of this patent

Method and apparatus for manufacture of magnetizable microparticles

Life of this patent

Abstract

Claims39