PRODUCT AND PROCESS

• US 20130157013A1
• Filed: 06/07/2011
• Published: 06/20/2013
• Est. Priority Date: 06/07/2010
• Status: Active Grant

• Current Assignee: University of The West of England Bristol
• Original Assignee: University of The West of England Bristol
• Inventors: Huson, David, Hoskins, Stephen
• Granted Patent: US 8,962,507 B2
• Time in Patent Office: Days
• US Class Current: 428/156
• CPC Class Codes: B28B 1/00 Producing shaped prefabricated articles from the material using presses B28B3/00; shaping on moving conveyors B28B5/00; producing tubular articles B28B21/00 ; producing articles with embedded elements B28B23/00
• CPC Class Codes: B28B 1/001 Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material selective deposition modelling of metallic powder B22F10/00; rapid manufacturing of 3D objects in general and in particular of plastics B29C64/00
• CPC Class Codes: B28B 7/465 Applying setting liquid to dry mixtures
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: C04B 2235/321 Dolomites, i.e. mixed calcium magnesium carbonates
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3244 Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3418 Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint glass constituents C04B2235/36
• CPC Class Codes: C04B 2235/3454 Calcium silicates, e.g. wollastonite
• CPC Class Codes: C04B 2235/3463 Alumino-silicates other than clay, e.g. mullite
• CPC Class Codes: C04B 2235/5212 Organic
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/6026 Computer aided shaping, e.g. rapid prototyping
• CPC Class Codes: C04B 2235/606 Drying
• CPC Class Codes: C04B 2235/616 Liquid infiltration of green bodies or pre-forms
• CPC Class Codes: C04B 2235/94 Products characterised by their shape
• CPC Class Codes: C04B 2237/341 Silica or silicates
• CPC Class Codes: C04B 33/00 Clay-wares monolithic refractories or refractory mortars C04B35/66; porous products C04B38/00
• CPC Class Codes: C04B 33/34 : combined with glazing
• CPC Class Codes: C04B 35/18 : rich in aluminium oxide
• CPC Class Codes: C04B 35/62665 : Flame, plasma or melting treatment
• CPC Class Codes: C04B 35/6316 : Binders based on silicon compounds
• CPC Class Codes: C04B 35/632 : Organic additives
• CPC Class Codes: C04B 35/6365 : Cellulose or derivatives thereof
• CPC Class Codes: Y10T 428/24479 : including variation in thickness
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]

Abstract

The invention relates to a composition, which comprises a particulate mixture of: (i) 25 to 80% calcined clay; (ii) 5 to 70% fluxing component; and (iii) 5 to 70% filler component.

Claims

1. A composition, which comprises a particulate mixture of:

(i) 25 to 80% calcined clay;

(ii) 5 to 70% fluxing component; and

(iii) 5 to 70% filler component.

2. A composition according to claim 1, wherein the mean particle diameter of the particulate mixture is 100 μ

m or below, preferably 30 to 100 μ

m, more preferably 30 to 50 μ

m.

3. A composition according to claim 1, wherein the composition additionally comprises cellulose fibres, preferably wherein the cellulose fibres are present at a concentration of between 5 and 50% of the composition.

4. A composition according to claim 3 in which the cellulose fibres are present at a concentration of between 5 and 10% of the composition.

5. A composition according to claim 1, wherein the composition additionally comprises an acid in particulate form, preferably wherein the acid is present at a concentration of between 3 and 10% of the composition, and most preferably wherein the acid is citric acid.

6. A composition according to claim 1, wherein the composition comprises 40 to 65% calcined clay, preferably wherein the composition comprises 45 to 55% calcined clay.

7. A composition according to claim 1, wherein the calcined clay comprises china clay, ball clay, fire clay, earthenware clay or stoneware clay which has been calcined, preferably wherein the calcined clay is china clay that has been calcined.

8. A composition according to claim 1, wherein the composition comprises 10 to 45% fluxing component, preferably wherein the composition comprises 15% to 25% fluxing component.

9. A composition according to claim 1, wherein the fluxing component is a feldspar, Wollstonite or dolomite type flux.

10. A composition according to claim 1, wherein the composition comprises 20 to 50% filler component, preferably wherein the composition comprises 25 to 35% filler component.

11. A composition according to claim 1, wherein the filler component comprises silica, preferably wherein the filler component comprises silica in crystalline or fused form.

12. A composition according to claim 1, wherein the filler component comprises alumina in particulate form, preferably wherein the alumina is present at a concentration of between 1 and 10% of the composition.

13. A composition according to claim 1, which comprises 45 to 55% calcined china clay, 15 to 30% silica, 15 to 30% feldspar, 5 to 15% cellulose, and 2 to 8% citric acid.

14. A composition according to claim 1, which comprises a metal oxide selected from the group comprising cobalt oxides, ferric oxides, manganese dioxides and copper oxides.

15. A method of making an object, the method comprising the steps of:

(a) providing a composition comprising a particulate mixture of;

(i) 25 to 80% calcined clay;

(ii) 5 to 70% fluxing component; and

(iii) 5 to 70% filler component;

(b) spreading a quantity of the composition in a layer;

(c) applying a binder to selected regions of the layer and causing the composition to become bonded in the selected regions;

(d) repeating steps (b) and (c) to produce successive layers of composition and selected regions of bonded composition in each layer, wherein the selected regions of bonded composition in successive layers are bonded to one another; and

(e) removing unbonded composition from the bonded composition to provide the object.

17. A method according to claim 15, wherein the bonded and unbonded composition are subjected to a drying step prior to step (e), preferably wherein the drying step involves heating the bonded and unbonded composition to at least 40°

C., preferably at least 60°

C., more preferably between 70 and 120°

C.

18. A method according to claim 15, wherein the binder is a liquid binder, preferably wherein the binder comprises silica, more preferably wherein the binder comprises colloidal silica and the composition comprises citric acid.

19. A method according to claim 15, in which the binder includes water and alcohol.

20. A method according to claim 15, additionally comprising the steps of:

(f) drying the object;

(g) firing the object;

(h) glazing the object to provide a glazed object; and

(i) firing the glazed object.

21. A method according to claim 15, additionally comprising the step of applying to the object an infiltrate, preferably wherein the infiltrate comprises sodium silicate or a colloidal suspensions of silica, alumina or zirconia.

22. A method according to claim 15, wherein the object is:

an item of crockery, preferably a bowl, plate, cup, or teapot;

a vase;

a figure;

a bust;

a paperweight;

another decorative object;

a mould;

or a tile.

23. A method according to claim 15, wherein the selected regions to which binder is applied are arranged so that more than one object is provided, preferably wherein the object is a tile and more than one tile is provided, more preferably wherein at least 10 tiles are provided, more preferably wherein 50 to 200 tiles are provided.

24. A method according to claim 15, wherein the object is designed using a computer aided design program, and steps (b), (c) and (d) of the method are controlled by the computer program.

25. A method according to claim 24, wherein the object comprises a three-dimensional surface which is a representation of a two-dimensional image, and a computer program is used to generate data corresponding to the three-dimensional surface from the two-dimensional image.

26. A method according to claim 24, wherein the two-dimensional image is derived from a photograph, painting or print, and the object is a tile with a three-dimensional contoured surface that represents the two-dimensional image.

27. A method according to claim 26, wherein the tile is provided with a glaze which overlays the contoured surface, preferably wherein the outer surface of the glaze is substantially planar.

28. A method according to claim 29, wherein the glaze is transparent, partially transparent or translucent.

29. A product which comprises an object made by the process of claim 15.

16. (canceled)