Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
192 words
In a thin web of non-woven carbon fibers suitable for use as a substrate in fuel cell electrodes, the improvement wherein the web is impregnated with from 0.05 kg. to 0.5 kg. of a fused hydrophobic resin per square meter of web, which resin serves to increase the structural integrity and hydrophobicity of the web, and the web has been produced by spinning carbonaceous pitch fiber having a mesophase content of from 40 percent by weight to 90 percent by weight from a nonthixotropic carbonaceous pitch having a mesophase content of from 40 percent by weight to 90 percent by weight and which, under quiescent conditions, forms a homogeneous bulk mesophase having large coalesced domains, disposing staple lengths of the spun fiber in intimately contacting relationship with each other in a non-woven fibrous web, heating the web produced in this manner in an oxidizing atmosphere to thermoset the fibers to an extent which will allow the fibers to maintain their shape upon heating to more elevated tepmperatures, and further heating the web containing the thermoset fibers to a carbonizing temperature in an oxygen-free atmosphere so as to expel hydrogen and other volatiles.
Claim 2
Dependent Claim
192 words
In a thin web of non-woven carbon fibers suitable for use as a substrate in fuel cell electrodes, the improvement wherein the web is impregnated with from 0.05 kg. to 0.5 kg. of a fused hydrophobic resin per square meter of web, which resin serves to increase the structural integrity and hydrophobicity of the web, and the web has been produced by spinning carbonaceous pitch fiber having a mesophase content of from 40 percent by weight to 90 percent by weight from a nonthixotropic carbonaceous pitch having a mesophase content of from 40 percent by weight to 90 percent by weight and which, under quiescent conditions, forms a homogeneous bulk mesophase having large coalesced domains, disposing staple lengths of the spun fiber in intimately contacting relationship with each other in a non-woven fibrous web, heating the web produced in this manner in an oxidizing atmosphere to thermoset the fibers to an extent which will allow the fibers to maintain their shape upon heating to more elevated tepmperatures, and further heating the web containing the thermoset fibers to a carbonizing temperature in an oxygen-free atmosphere so as to expel hydrogen and other volatiles.
Claim 3
Dependent Claim
16 words
A substrate as in claim 1 coated with a catalytically active metal to form an electrode.
Claim 4
Dependent Claim
15 words
An electrode as in claim 2 wherein the catalytically active metal is a noble metal.
Claim 5
Dependent Claim
12 words
An electrode as in claim 3 wherein the noble metal is platinum.
Claim 6
Dependent Claim
16 words
A substrate as in claim 1 wherein the hydrophobic resin is impregnated with a carbonaceous flour.
Claim 7
Dependent Claim
16 words
A substrate as in claim 5 coated with a catalytically active metal to form an electrode.
Claim 8
Dependent Claim
15 words
An electrode as in claim 6 wherein the catalytically active metal is a noble metal.
Claim 9
Dependent Claim
12 words
An alectrode as in claim 7 wherein the noble metal is platinum.
Claim 10
Dependent Claim
13 words
A substrate as in claim 5 wherein the carbonaceous flour is activated carbon.
Claim 11
Dependent Claim
16 words
A substrate as in claim 9 coated with a catalytically active metal to form an electrode.
Claim 12
Dependent Claim
15 words
An electrode as in claim 10 wherein the catalytically active metal is a noble metal.
Claim 13
Dependent Claim
12 words
An electrode as in claim 11 wherein the noble metal is platinum.
Claim 14
Dependent Claim
12 words
A substrate as in claim 1 wherein the hydrophobic resin is polytetrafluoroethylene.
Claim 15
Dependent Claim
16 words
A substrate as in claim 13 coated with a catalytically active metal to form an electrode.
Claim 16
Dependent Claim
15 words
An electrode as in claim 14 wherein the catalytically active metal is a noble metal.
Claim 17
Dependent Claim
12 words
An electrode as in claim 15 wherein the noble metal is platinum.
Claim 18
Dependent Claim
21 words
A substrate as in claim 13 which contains from 0.06 kg. to 0.12 kg. of polytetrafluoroethylene per square meter of web.
Claim 19
Dependent Claim
16 words
A substrate as in claim 17 coated with a catalytically active metal to form an electrode.
Claim 20
Dependent Claim
15 words
An electrode as in claim 18 wherein the catalytically active metal is a noble metal.
Claim 21
Dependent Claim
12 words
An electrode as in claim 19 wherein the noble metal is platinum.
Claim 22
Dependent Claim
16 words
A substrate as in claim 13 wherein the polytetrafluoroethylene resin is impregnated with a carbonaceous flour.
Claim 23
Dependent Claim
16 words
A substrate as in claim 21 coated with a catalytically active metal to form an electrode.
Claim 24
Dependent Claim
15 words
An electrode as in claim 22 wherein the catalytically active metal is a noble metal.
Claim 25
Dependent Claim
12 words
An electrode as in claim 23 wherein the noble metal is platinum.
Claim 26
Dependent Claim
13 words
A substrate as in claim 21 wherein the carbonaceous flour is activated carbon.
Claim 27
Dependent Claim
16 words
A substrate as in claim 25 coated with a catalytically active metal to form an electrode.
Claim 28
Dependent Claim
15 words
An electrode as in claim 26 wherein the catalytically active metal is a noble metal.
Claim 29
Dependent Claim
12 words
An electrode as in claim 27 wherein the noble metal is platinum.