A METHOD OF GENERATING A MOLD AND USING IT FOR PRINTING A THREE-DIMENSIONAL OBJECT
This invention relates to three-dimensional printing. This invention in particular relates to a method of generating mold and printing a three-dimensional object. The mold thickness is controlled and holes are generated in the mold surface for releasing moisture easily. The mold surface having holes is designed initially digitally and then combined with the three-dimensional model before printing the three-dimensional object. In case the thickness of the mold surface is more then it reduces the overall quality of the three-dimensional object. When the model is enclosed inside the mold, there will be some residue moisture in the model even if the drying apparatus can improve this by drying layer by layer. This affects the final quality of the part. A solution of these problems is provided in the present invention. The thickness of the mold layer is between 0.5 to 1 mm and holes having 0.1 to 0.4 mm diameter. The holes are evenly distributed on the mold. The mold having the holes is prepared from which moisture can easily escape. A method of digitally generated a mold having thin layer and holes is used for fabricating three dimensional objects with high precision and quality.
1 . A mold for a three-dimensional object printed from a crafting medium, said mold comprising:
(a) one or more mold layers,
wherein each of the one or more mold layers substantially surrounds a corresponding crafting medium layer (b) of the object.
2 . The mold according to claim 1 wherein the one or more mold layers substantially conform to the shape of the object.
3 . The mold according to claim 1 wherein the mold layer comprises a thermoplastic polymer.
4 . The mold according to claim 3 wherein the thermoplastic polymer is selected from the group consisting of poly(propylene), poly(styrene), poly(lactic acid) (PLA), acrylonitrilebutadiene-styrene (ABS), polycarbonate abs (PC-ABS), nylon, poly(carbonate), poly(phenyl sulfone), ultem, poly(ethylene), acrylic [poly(methyl methacrylate)], poly(benzimidazole), poly(ether sulfone), poly(etherether ketone), poly(etherimide), poly(phenylene oxide), poly(phenylene sulfide), poly(vinyl chloride), poly(vinyldiene fluoride), poly(acetal), poly(vinyl acetate), poly(vinyl butyrate), poly(vinyl alcohol), poly(4-hydroxystyrene), poly(vinyl formate), poly(vinyl stearate), poly(acrylamide), poly(caprolactone), chitosan and combinations thereof.
5 . The mold according to claim 1 , wherein said mold has a skin thickness from about 0.1 to about 10 mm.
6 . The mold according to claim 1 , wherein said mold has a skin thickness from about 0.2 to about 2 mm.
7 . The mold according to claim 1 , wherein said mold has a skin thickness from about 0.5 to about 1 mm.
8 . The mold according to claim 1 , wherein said mold comprises one or more perforations.
9 . The mold according to claim 8 wherein said one or more perforations have a diameter from about 0.1 mm to about 0.4 mm.
10 . The mold according to claim 1 wherein the crafting medium comprises:
(i) from about 40% to about 80% by volume basis of a powder selected from the group consisting of metal powders, ceramic powders, and combinations, thereof;
(ii) from about 0.5% to about 10% by volume of a binder; and
(iii) from about 15% to about 60% by volume of an aqueous solvent.
11 . The mold according to claim 1 wherein the crafting medium comprises:
(i) from about 40% to about 80% by volume basis of a powder selected from the group consisting of metal powders, ceramic powders, and combinations, thereof;
(ii) from about 0.5% to about 10% by volume of a binder; and
(iii) from about 15% to about 60% by volume of a non-aqueous solvent.
12 . The mold according to claim 10 wherein the metal or ceramic powder of the crafting medium comprises particles having a size in the range from 0.1-100 micrometers.
13 . The mold according to claim 10 wherein the metal powder of the crafting medium is selected from the group consisting of silver, gold, copper, tin, nickel, chromium, zinc, tungsten, cobalt, aluminum, molybdenum, boron, iron, titanium, vanadium, niobium, silicon, manganese, steel, metal alloys, and combinations thereof.
14 . The mold according to claim 10 wherein the ceramic powder of the crafting medium is selected from the group consisting of silicon carbide, boron carbide, aluminum carbide, tungsten carbide, titanium carbide, tantalum carbide, silicon nitride, boron nitride, aluminum nitride, titanium nitride, zirconium nitride, steatite, forsterite, alumina, zircon beryllia, magnesia, mullite, cordierite, aluminum titanate, zirconia, and combinations thereof.
15 . The mold according to claim 10 wherein the binder is selected from the group consisting of organic binders, inorganic binders, and combinations thereof.
16 . The mold according to claim 15 wherein the in organic binder is selected from the group consisting of epoxy, polyurethane, agar-agar, starch, cellulosic materials, arrow root, Agar (E406), Alginic acid (E400), Sodium alginate (E401), Carrageenan (E407), Gum arabic (E414), Gum ghatti, Gum tragacanth (E413), Karaya gum (E416), Guar gum (E412), Locust bean gum (E410), Beta-glucan, Chicle gum, Dammar gum, Glucomannan (E425), Mastic gum, Psyllium seed husks, Spruce gum, Tara gum (E417), Gellan gum (E418), Xanthan gum (E415), polyethylene oxide, polycarboxylic acids (polyacrylic acid), polycarboxylates, polyvinyl alcohol, cellulose gum (Aquacel GSA and Aquacel GSH), hydroxymethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, and combinations thereof.
17 . The mold according to claim 15 wherein the inorganic binder is selected magnesium oxide, magnesic, cement, sorel cement, inorganic salts, and combinations thereof.
18 . The mold according to claim 10 wherein said aqueous solvent is selected from the group consisting of water, or water in combination with one or more non-aqueous solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, acetone, acetaldehyde, ethyl acetate, C2-C4 diols, glycerol, acetonitrile, and mixtures thereof.
19 . The mold according to claim 11 wherein said non-aqueous solvent is selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, acetone, acetaldehyde, ethyl acetate, C2-C4 diols, glycerol, acetonitrile, and mixtures thereof.
20 . The mold according to claim 1 wherein each of the one or more mold layers comprises a structural additive that substantially prevents undesired fusing of an area of the crafting medium to a further area of the crafting medium during subsequent sintering of the object.
21 . The mold according to claim 20 wherein the structural additive is selected from the group consisting of metal particles, ceramic particles, charcoal particles and combinations thereof.
22 . The mold according to claim 21 wherein the metal particles are selected from the group consisting of silver, gold, copper, tin, nickel, chromium, zinc, tungsten, cobalt, aluminum, molybdenum, boron, iron, titanium, vanadium, niobium, silicon, manganese, steel, metal alloys, and combinations thereof.
23 . The mold according to claim 21 wherein the ceramic particles are selected from the group consisting of silicon carbide, boron carbide, aluminum carbide, tungsten carbide, titanium carbide, tantalum carbide, silicon nitride, boron nitride, aluminum nitride, titanium nitride, zirconium nitride, steatite, forsterite, alumina, zircon beryllia, magnesia, mullite, cordierite, aluminum titanate, zirconia, and combinations thereof.
24 . An object prepared using the mold of claim 1 .
25 . The object according to claim 24 prior to sintering.
26 . A method for three-dimensionally printing a paste-based crafting model comprising the steps of:
(a) depositing a mold layer from a print head, said mold layer having a skin thickness from about 0.1 mm to about 10 mm, and
(b) depositing a layer of a crafting medium from a print head within the confines of the mold layer.
27 . The method for according to claim 24 further comprising the step of
(c) drying the deposited layer from step (b) with a drying means.
28 . The method according to claim 27 wherein steps (a), (b), and (c) are performed prior to deposition of a further crafting medium layer.