Recycling of scrap dental zirconia block

Patent metadata

Field	Value
Publication number	US-2024262706-A1
Application number	US-202418428929-A
Country	US
Kind code	A1
Filing date	Jan 31, 2024
Priority date	Feb 3, 2023
Publication date	Aug 8, 2024
Grant date	—

Abstract

A method that includes collecting scrap ZrO2 material; reducing sizes of the scrap ZrO2 material to produce a reduced-size scrap ZrO2 material; preparing a ceramic slurry comprising the reduced-size scrap ZrO2 material, deionized water, and at least one dispersant; milling the ceramic slurry to produce a milled ZrO2 slurry, wherein the milled ZrO2 slurry comprises a ZrO2 powder with a particle size distribution D(50) of 0.05 μm to 1.0 μm; and casting the milled ZrO2 slurry to prepare a ceramic block.

First claim

What is claimed is:

1 . A method, comprising:
collecting scrap ZrO 2 material; reducing sizes of the scrap ZrO 2 material to produce a reduced-size scrap ZrO 2 material; preparing a ceramic slurry comprising the reduced-size scrap ZrO 2 material, deionized water, and at least one dispersant; milling the ceramic slurry to produce a milled ZrO 2 slurry, wherein the milled ZrO 2 slurry comprises a ZrO 2 powder with a particle size distribution D (50) of 0.05 μm to 1.0 μm; and casting the milled ZrO 2 slurry to prepare a ceramic block.

2 . The method of claim 1 , further comprising sieving the reduced-size scrap ZrO 2 material.

3 . The method of claim 1 , wherein the reduced-size ZrO 2 material comprises ZrO 2 particles with a particle size distribution D (50) of 1 mm to 10 mm.

4 . The method of claim 2 , wherein the sieved, reduced-size ZrO 2 material comprises ZrO 2 particles with a particle size of 0.0013 mm to 8 mm.

5 . The method of claim 1 , wherein reducing sizes of the scrap ZrO 2 material comprises milling the scrap ZrO 2 material using a mechanical milling process.

6 . The method of claim 1 , wherein the milling of the ceramic slurry comprises wet ball milling.

7 . The method of claim 6 , wherein the wet ball milling comprises using a mixture of 5 mm and 20 mm diameter balls.

8 . The method of claim 6 , wherein the wet ball milling comprises using 5 mm diameter balls.

9 . The method of claim 6 , wherein the wet ball milling is performed for 10 hours.

10 . The method of claim 1 , wherein reducing sizes of the scrap ZrO 2 material comprises roll crushing, and the milling of the ceramic slurry comprises wet milling or dry milling.

11 . The method of claim 1 , wherein the milled ZrO 2 slurry comprises a ZrO 2 powder with a particle size distribution D (50) of 0.1 μm to 0.5 μm.

12 . The method of claim 1 , further comprising sintering the ceramic block.

13 . The method of claim 1 , further comprising adding at least one binder to the ceramic slurry.

14 . The method of claim 1 , further comprising attrition milling the milled ZrO 2 slurry.

15 . The method of claim 14 , wherein the attrition milling is performed for one hour.

16 . The method of claim 1 , wherein the scrap ZrO 2 material is produced during a process for making a dental prosthetic device.

17 . The method of claim 12 , wherein the sintered ceramic block has a flexural strength of 700 to 1500 MPa, a fracture toughness of 1 to 8 MPa·m 1/2 ; and a transmittance of 30% to 65% at 700 nm (when measured on a 1 mm thick fully sintered ceramic body).

18 . The method of claim 12 , wherein the sintered ceramic block has a flexural strength of 900 to 1200 MPa, a fracture toughness of 3 to 5 MPa·m 1/2 ; and a transmittance of 40% to 55% at 700 nm (when measured on a 1 mm thick fully sintered ceramic body).

19 . The method of claim 12 , further comprising forming a dental prosthetic device from the sintered ceramic block.

20 . The method of claim 1 , wherein the ceramic block has a size of 90 mm to 115 mm.

Assignees

• Glidewell James R Dental Ceramics Inc

Inventors

• Kim Dongkyu
• Balasubramanian Sreeram
• Gonzalez Hugo
• Campbell Mathew
• Malyala Rajashekharam

Classifications

• C09C3/041

  Grinding · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title

• C01G25/02 Primary

  Oxides · CPC title

• A61C13/0022

  Blanks or green, unfinished dental restoration parts · CPC title

• A61C13/0004 Primary

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