Westaim Technologies

Microwear Corporation

Other

Thermicedge Corporation

Prasad Shrikrishna Apte

Larry Roy Morris

Robert Edward Burrell

Kashmir Singh Gill

Stephen F Corbin

Sudhindra Bharat Sant

Roderick John Precht

Christine E Third

Ernesto S Tachauer

Travis Kyle Solomon

Anti-microbial coatings and method of forming same on medical devices are provided. The coatings are preferably formed by depositing an anti-microbial, biocompatible metal by vapor deposition techniques to produce atomic disorder in the coating such that a sustained release of metal ions sufficient to produce an anti-microbial effect is achieved. Preferred deposition conditions to achieve atomic disorder include a lower than normal substrate temperature, and one or more of a higher than normal working gas pressure and a lower than normal angle of incidence of coating flux. Anti-microbial powders formed by vapor deposition or altered by mechanical working to produce atomic disorder are also provided. Novel anti-microbial silver materials are defined, characterized by having a positive rest potential, a T.sub.rec /T.sub.m less than 0.33, and a grain size less than 200 nm. Anti-microbial fine grain or nanocrystalline materials are provided, together with methods of preparation, wherein the anti-microbial metal if deposited in a matrix with atoms or molecules of a different material such as other biocompatible metals (ex. Ta), trapped or absorbed oxygen, or compounds of anti-microbial metals or biocompatible metals (ex. Ag0 or TaO).

Anti-microbial materials

Production of an anti-microbial effect in an alcohol or water based electrolyte is achieved by preparing silver materials that form complex ions other than Ag.sup.+, Ag.sup.2+, or Ag.sup.3+, and which produce an anti-microbial effect that is greater than that produced by an equivalent amount of silver as Ag.sup.+. Exemplary complex silver ions produced include Ag(CN).sub.2.sup.-, AgCN(.sub.aq)(ion pair), Ag(NH.sub.3).sub.2.sup.+, AgCl.sub.2.sup.-, Ag(OH).sub.2.sup.-, Ag.sub.2 (OH).sub.3.sup.-, Ag.sub.3 (OH).sub.4.sup.-, and Ag(S.sub.2 O.sub.3).sub.2.sup.3-. The silver materials may be prepared as powders or as solutions or suspensions containing the complex silver ions. The silver materials might also be prepared as coatings, foils, powders, or fine grain or nanocrystalline powders, which are formed with atomic disorder to provide sustained release of the complex silver ions.

Process for producing anti-microbial effect with complex silver ions

Anti-microbial coatings and method of forming same on medical devices are provided. The coatings are preferably formed by depositing an anti-microbial, biocompatible metal by vapour deposition techniques to produce atomic disorder in the coating such that a sustained release of metal ions sufficient to produce an anti-microbial effect is achieved. Preferred deposition conditions to achieve atomic disorder include a lower than normal substrate temperature, and one or more of a higher than normal working gas pressure and a lower than normal angle of incidence of coating flux. Anti-microbial powders formed by vapour deposition or altered by mechanical working to produce atomic disorder are also provided. Novel anti-microbial silver materials are defined, characterized by having a positive rest potential, a T.sub.rec /T.sub.m less than 0.33, and a grain size less than 200 nm. Anti-microbial fine grain or nanocrystalline materials are provided, together with methods of preparation, wherein the anti-microbial metal if deposited in a matrix with atoms or molecules of a different material such as other biocompatible metals (ex. Ta), trapped or absorbed oxygen, or compounds of anti-microbial metals or biocompatible metals (ex. Ag0 or TaO).

Novel processes are provided for the production of porous ceramic preforms, metal activated porous ceramic preforms and intermetallic/ceramic/metal composites. These products are all manufactured using processes which are based on tape casting techniques.

Method of manufacturing intermetallic/ceramic/metal composites

A microwave susceptor bed useful for sintering ceramics, ceramic composites and metal powders is disclosed. The susceptor bed contains granules of a major amount of a microwave susceptor material, and a minor amount of a refractory parting agent, either dispersed in the susceptor material, or as a coating on the susceptor material. Alumina is the preferred susceptor material. Carbon is the most preferred parting agent. A sintering process using the bed and novel silicon nitride products produced thereby are described.

Sintered silicon nitride product

A process is provided for the manufacture of porous metal components. The process involves preparing a colloidal suspension comprising a metal-containing powder in admixture with a binder system, and a plasticizer in an organic solvent. Optionally, a particulate pore forming agent may be added to the suspension. The suspension is cast into a thin sheet and air dried to thereby form a tape. The tapes are layered and formed by compacting at predetermined pressures to laminate the tapes, thus forming a green body. Optionally, a second pore-forming agent may be introduced between, or associated with, the tape layers. The green body is heated at a controlled rate to form a brown body, and finally sintered under controlled conditions to produce the finished component.

Porous metal structures and processes for their production

Anti-microbial coatings and method of forming same on medical devices are provided. The coatings are preferably formed by depositing an anti-microbial, biocompatible metal by vapor deposition techniques to produce atomic disorder in the coating such that a sustained release of metal ions sufficient to produce an anti-microbial effect is achieved. Preferred deposition conditions to achieve atomic disorder include a lower than normal substrate temperature, and one or more of a higher than normal working gas pressure and a lower than normal angle of incidence of coating flux. Anti-microbial powders formed by vapor deposition or altered by mechanical working to produce atomic disorder are also provided. Novel anti-microbial silver materials are defined, characterized by having a positive rest potential, a T.sub.rec /T.sub.m less than 0.33, and a grain size less than 200 nm. Anti-microbial fine grain or nanocrystalline materials are provided, together with methods of preparation, wherein the anti-microbial metal if deposited in a matrix with atoms or molecules of a different material such as other biocompatible metals (ex. Ta), trapped or absorbed oxygen, or compounds of anti-microbial metals or biocompatible metals (ex. AgO or TaO).

Microwave sintering process

A microwave susceptor bed useful for sintering ceramics, ceramic composites and metal powders is described. The susceptor bed includes granules of a major amount of a microwave susceptor material, and a minor amount of a refractory parting agent, either dispersed in the susceptor material, or as a coating on the susceptor material. Alumina is the preferred susceptor material. Carbon is the most preferred parting agent. Also described is a sintering process using the bed and to novel silicon nitride products produced thereby.

A process is provided for the manufacture of thin walled ceramic structures, particularly conical or near conical shaped structures. The process involves a tape casting technique wherein a green tape is prepared from a colloidal suspension containing a ceramic powder, a binder system, a plasticizer and a solvent. The suspension is cast into a thin sheet and dried to form a pliable tape. The tape is cut into planar, shaped pieces. Non-planar components of the final structure are preformed from the cut planar tape pieces into predetermined three dimensional shapes. The planar and preformed components are sequentially assembled within a die and compacted under pressure to form a green body. The green body is subjected first, to a burnout cycle to form a brown body, and then sintered to form the unitary, cohesive, thin walled ceramic structure.

Growing community of inventors

St. Albert, Canada

Prasad Shrikrishna Apte