US4900698A — Ceramic product and process

Claim 1

Independent Claim 169 words

Homogeneous precursor composition for forming a sintered porous ceramic article comprising (a) 5 to 90 wt. % of a finel divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof, (b) 5 to 90 wt. % of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a), and (c) remainder of a particle binding effective amount of a nonaqueous polymer binder system which is capable of being removed when the composition is heated in the pressure of air or oxygen, said binder being present in at least 4% by weight of the composition and comprising a mixture of (1) a polymer which is capable of being oxidized away when the composition is heated and (2) a plasticizer for the polymer.

Claim 2

Dependent Claim 169 words

Homogeneous precursor composition for forming a sintered porous ceramic article comprising (a) 5 to 90 wt. % of a finel divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof, (b) 5 to 90 wt. % of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a), and (c) remainder of a particle binding effective amount of a nonaqueous polymer binder system which is capable of being removed when the composition is heated in the pressure of air or oxygen, said binder being present in at least 4% by weight of the composition and comprising a mixture of (1) a polymer which is capable of being oxidized away when the composition is heated and (2) a plasticizer for the polymer.

Claim 3

Dependent Claim 18 words

Composition according to claim 1 in which the ceramic filler is an oxide of the metal in (a).

Claim 4

Dependent Claim 45 words

Composition according to claim 1 in which the metal of (a) is a member of the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, the rare earth metals and mixtures thereof.

Claim 5

Dependent Claim 26 words

Composition according to claim 1 in which the metal of (a) is a member of the group consisting of Tl, Pb, Mo, W and mixtures thereof.

Claim 6

Dependent Claim 35 words

Composition according to claim 1, wherein (c) the polymer is present from 1 to 15 wt. % of the composition; and (d) the plasticizer is present from 3 to 60 wt. % of the composition.

Claim 7

Dependent Claim 24 words

Composition according to claim 5, wherein the polymer is selected from the group consisting of polyolefin, polyvinyl chloride, polyvinyl acetate, polystyrene and mixtures thereof.

Claim 8

Dependent Claim 11 words

Composition according to claim 6, wherein the polymer is a polyolefin.

Claim 9

Dependent Claim 18 words

Composition according to claim 7 in which the ceramic filler is an oxide of the metal in (a).

Claim 10

Dependent Claim 45 words

Composition according to claim 7 in which the metal of (a) is a member of the group consisting of Al, Zn, Cu, Fe, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, the rare earth metals and mixtures thereof.

Claim 11

Dependent Claim 26 words

Composition according to claim 7 in which the metal of (a) is a member of the group consisting of Tl, Pb, Mo, W and mixtures thereof.

Claim 12

Dependent Claim 11 words

Composition according to claim 9 in which the metal is Al.

Claim 13

Dependent Claim 16 words

Composition according to claim 9 in which the metal is in the form of atomized spheroids.

Claim 14

Dependent Claim 12 words

Composition according to claim 11 in which the ceramic filler is alumina.

Claim 15

Dependent Claim 12 words

Composition according to claim 11 in which the ceramic filler is titania.

Claim 16

Dependent Claim 17 words

Composition according to claim 11 in which the ceramic filler is a mixture of alumina and titania.

Claim 17

Dependent Claim 13 words

Composition according to claim 7 in which the plasticizer is a mineral oil.

Claim 18

Dependent Claim 21 words

Composition according to claim 13 in which the polyolefin is a linear polyethylene having a molecular weight of at least 100,000.

Claim 19

Dependent Claim 27 words

Composition according to claim 13 in which the metal is 15-40, the ceramic filler is 40-70, the polyolefin is 2-10, and the plasticizer is 8-30 wt %.

Claim 20

Dependent Claim 37 words

Composition according to claim 18 in which the metal is atomized Al; the ceramic filler is alumina; the polyolefin is a linear polyethylene having a molecular weight of at least 100,000; and the plasticizer is mineral oil.

Claim 21

Dependent Claim 133 words

Homogeneous porous greenware composition consisting essentially of, in parts by weight: (a) 5 to 90 of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof; (b) 5 to 90 of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a); and (c) 1 to 15 of a binder comprising a polymer which is capable of being oxidized away when the composition is heated, said binder previously having contained a plasticizer which has been essentially removed to create the porous greenware composition.

Claim 22

Dependent Claim 133 words

Homogeneous porous greenware composition consisting essentially of, in parts by weight: (a) 5 to 90 of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof; (b) 5 to 90 of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a); and (c) 1 to 15 of a binder comprising a polymer which is capable of being oxidized away when the composition is heated, said binder previously having contained a plasticizer which has been essentially removed to create the porous greenware composition.

Claim 23

Dependent Claim 12 words

Composition according to claim 20, in which the binder is a polyolefin.

Claim 24

Dependent Claim 24 words

Composition according to claim 21 in which the metal is 15-40, the ceramic filler is 40-70, and the polyolefin is 2-10 parts by weight.

Claim 25

Dependent Claim 16 words

Composition according to claim 22 in which the metal is in the form of atomized spheroids.

Claim 26

Dependent Claim 30 words

Composition according to claim 23 in which the metal is Al, the ceramic filler is alumina, and the polyolefin is linear polyethylene having a molecular weight of at least 100,000.

Claim 27

Dependent Claim 111 words

Sintered porous ceramic article consisting essentially of particles of ceramic filler having oxidized metal in the interstices thereof and bonding the filler particles, said article having been made from a mixture of metal particles selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, B, Ta, U, Cr, Co, v, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof and ceramic filler particles which are oxides of metals selected from the group listed above and characterized by the substantial conversion of the metal particles over a period of time to form said oxidized metal with substantially no unoxidized metal remaining.

Claim 28

Dependent Claim 111 words

Sintered porous ceramic article consisting essentially of particles of ceramic filler having oxidized metal in the interstices thereof and bonding the filler particles, said article having been made from a mixture of metal particles selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, B, Ta, U, Cr, Co, v, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof and ceramic filler particles which are oxides of metals selected from the group listed above and characterized by the substantial conversion of the metal particles over a period of time to form said oxidized metal with substantially no unoxidized metal remaining.

Claim 29

Dependent Claim 18 words

Article according to claim 25 in which the ceramic filler is alumina and the oxidized metal is Al.

Claim 30

Dependent Claim 22 words

Article according to claim 26 in which the weight ratio of oxidized Al to ceramic filler alumina is about 28-75 to 40-70.

Claim 31

Dependent Claim 33 words

Article according to claim 25, selected from the group consisting of microfilters, catalyst monoliths, catalyst pellets, tubes, hollow fibers, electronic substrates, turbine rotors, turbine blades, cylinder linings, piston tops, valve seats, and bricks.

Claim 32

Dependent Claim 139 words

Process comprising firing greenware which is a porous homogeneous mixture consisting essentially of, in parts by weight: (a) 5 to 90 of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof; (b) 5 to 90 of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a); and (c) 1 to 15 of a binder comprising a polymer which is capable of being oxidized away when the composition is heated, said binder previously having contained a plasticizer which has been essentially removed to create the porous greenware composition.

Claim 33

Dependent Claim 139 words

Process comprising firing greenware which is a porous homogeneous mixture consisting essentially of, in parts by weight: (a) 5 to 90 of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, T1, Pb, Mo, W, the rare earth metals and mixtures thereof; (b) 5 to 90 of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a); and (c) 1 to 15 of a binder comprising a polymer which is capable of being oxidized away when the composition is heated, said binder previously having contained a plasticizer which has been essentially removed to create the porous greenware composition.

Claim 34

Dependent Claim 12 words

Process according to claim 29, in which the binder is a polyolefin.

Claim 35

Dependent Claim 24 words

Process according to claim 30 in which the metal is 15-40, the ceramic filler is 40-70, and the polyolefin is 2-10 parts by weight.

Claim 36

Dependent Claim 16 words

Process according to claim 31 in which the metal is in the form of atomized spheroids.

Claim 37

Dependent Claim 32 words

Process according to claim 32 in which the metal is Al, the ceramic filler is alumina, and the polyolefin is particle form linear polyethylene having a molecular weight of at least 100,000.

Claim 38

Dependent Claim 56 words

Process according to claim 33 in which the firing is carried out in the following steps: about 6 hours increasing from room temperature to about 610° C., hold at about 610° C. for about 6 hours, then heat for about 1 hour to about 1450° C., and hold at about 1450° C. for about 2 hours.

Claim 39

Dependent Claim 163 words

Process comprising: (1) forming a homogenous composition consisting essentially of: (a) 5 to 90 wt. % of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, Tl, Pb, Mo, W, the rare earth metals and mixtures thereof, (b) 5 to 90 wt. % of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a), (c) 3 to 60 wt. % of a plasticizer, and (d) 1 to 15 wt. % of a polyolefin; (2) forming the composition of (1) into a desired shape; (3) removing most of the plasticizer from the shape thereby to form porous greenware; and (4) firing the greenware, thereby to remove polyolefin and any residual plasticizer, to sinter the ceramic filler, and to oxidize substantially all the metal.

Claim 40

Dependent Claim 163 words

Process comprising: (1) forming a homogenous composition consisting essentially of: (a) 5 to 90 wt. % of a finely divided solid metal capable of forming an oxide by heating in air and selected from the group consisting of Al, Zn, Fe, Cu, Si, Ti, Mg, Ba, Ta, U, Cr, Co, V, Mn, Ni, Sn, Zr, Th, Ge, Tl, Pb, Mo, W, the rare earth metals and mixtures thereof, (b) 5 to 90 wt. % of a finely divided ceramic filler which is an oxide of a metal selected from the group listed in part (a), (c) 3 to 60 wt. % of a plasticizer, and (d) 1 to 15 wt. % of a polyolefin; (2) forming the composition of (1) into a desired shape; (3) removing most of the plasticizer from the shape thereby to form porous greenware; and (4) firing the greenware, thereby to remove polyolefin and any residual plasticizer, to sinter the ceramic filler, and to oxidize substantially all the metal.

Claim 41

Dependent Claim 16 words

Process according to claim 35 in which the metal is in the form of atomized spheroids.

Claim 42

Dependent Claim 52 words

Process according to claim 35 in which in step (1) in weight % the metal is Al 15-40, the ceramic filler is alumina 40-70, the plasticizer is mineral oil 8-30, and the polyolefin is 2-10 and is particle form high molecular weight linear polyethylene having a molecular weight of at least 100,000.

Claim 43

Dependent Claim 48 words

Process according to claim 37 in which the firing is carried out in the following steps: 6 hours increasing from room temperature to 610° C., hold at 610° C. for 6 hours, then heat in 1 hour to 1450° C., and hold at 1450° C. for 2 hours.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1993-02-12	1993-08-14	1994-02-13	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1997-02-12	1997-08-14	1998-02-13	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2001-02-12	2001-08-14	2002-02-13	$7700.00	Window Closed / Lapsed

Ceramic product and process

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