Method of making a dental articles

Patent metadata

Field	Value
Publication number	US-11202694-B2
Application number	US-201615744930-A
Country	US
Kind code	B2
Filing date	Jul 11, 2016
Priority date	Jul 16, 2015
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

A method of making a dental article, has steps of (i) providing a layer of sinter powder, (ii) providing a solidifiable binder to form a circumferential fixation zone ( 114 ) which encloses a portion of the powder layer. The method further has the step of repeating steps (i) and (ii) with each fixation zone ( 114 ) of one layer being in contact with a fixation zone ( 114 ) of an adjacent layer such that a plurality of the fixation zones ( 114 ) together form a coherent hollow sleeve ( 116 ) extending across the layers. The corresponding plurality of powder portions in combination form a contiguous batch ( 118 ) of powder captured in the sleeve. The method facilitates the manufacturing of sintered dental articles.

First claim

What is claimed is:

1. A method of making a dental article precursor, comprising the steps of:
providing a base layer comprised of sinter powder and a solidified binder;
providing a sinter powder layer in contact with the base layer, the sinter powder layer having a thickness;
heating the solidified binder effective to provide a fluid solidifiable binder, the fluid solidifiable binder comprising coconut fat;
contacting the fluid solidifiable binder with the sinter powder layer, wherein the fluid solidifiable binder forms a circumferential fixation zone enclosing a portion of the sinter powder layer,
providing a successive sinter powder layer in contact with an adjacent sinter powder layer;
contacting the fluid solidifiable binder with the successive sinter powder layer, wherein the fluid solidifiable binder forms a circumferential fixation zone enclosing a portion of the successive sinter powder layer and contacts an adjacent circumferential fixation zone;
repeating the two immediate preceding steps for a determined number of times to provide a plurality of sinter powder layers that are at least partly enclosed by a plurality of circumferential fixation zones;
wherein the plurality of circumferential fixation zones together form a coherent sleeve extending across the plurality of sinter powder layers,
wherein the plurality of sinter powder layers together form a contiguous powder batch within the coherent sleeve, and
wherein formation of the coherent sleeve provides the dental article precursor.

2. The method of claim 1 , further comprising allowing the fluid solidifiable binders to solidify to provide the solidified binders.

3. The method of claim 1 , wherein the fluid solidifiable binder comprises a hardenable elastomer.

4. The method of claim 3 , further comprising irradiating the fluid solidifiable binder for conversion from a fluid state toward a solidified state by light and/or heat.

5. The method of claim 1 , wherein the fluid solidifiable binder is deposited on the sinter powder layer so as to form the circumferential fixation zone by soaking a circumferential portion of the sinter powder layer with the fluid solidifiable binder.

6. The method of claim 1 , further comprising providing a cover layer comprised of sinter powder and solidified binder, wherein the base layer, the cover layer and the coherent sleeve together form a closed shell which seals the contiguous powder batch therein.

7. The method of claim 1 , further comprising placing the contiguous powder batch in a bag.

8. The method of claim 1 , further comprising compacting the contiguous powder batch by pressing in an isostatic press.

9. The method of claim 8 , further comprising the step of firing the dental article precursor, thereby removing the binder.

10. The method of claim 1 , further comprising sintering the dental article precursor to provide a dental ceramic material or a dental glass-ceramic material.

11. The method of claim 10 , wherein the sinter powder layer(s) comprises sinter powder particles that are coated with a bonding agent, wherein the bonding agent has a higher temperature stability than the fluid solidifiable binder.

12. The method of claim 1 , further comprising providing the sinter powder layer with a coloring substance.

13. The method of claim 12 , further comprising providing the coloring substance to a determined sub-portion of the portion enclosed by the circumferential fixation zone.

14. The method of claim 12 , further comprising providing more than one coloring substances to determined sub-portions of the portion enclosed by the circumferential fixation zone, wherein the coloring substances are configured to exhibit or to convert into different colors.

Assignees

• 3M Innovative Properties Co

Inventors

• Korten Malte
• Mayr Helmar B
• Raia Gioacchino
• Oberpertinger Daniel D
• Goetzinger Martin
• Bissinger Peter

Classifications

• B29C64/20

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B29C64/165

  using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber · CPC title

• A61C13/0022 Primary

  Blanks or green, unfinished dental restoration parts · CPC title

• A61C13/0013

  using stereolithographic techniques · CPC title

• A61C13/0004

  Computer-assisted sizing or machining of dental prostheses · CPC title