Patent US4772455A successfully refreshed from Google Patents.
US4772455A
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Filter
Assignee: Teijin Ltd
•
Filing: 1985-04-05
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Granted: 1988-09-20
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Expires: 2005-04-05
Abstract
Abstract A filter composed of a mesh structure substrate having deposited thereon and therein activated carbon fiber treated with an alkali and having a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber, wherein the activated carbon fiber is adhered to the substrate by a binder, and wherein the activated carbon fiber is deposited on and in the substrate by impregnating the substrate with a dispersion obtained by dispersing activated carbon fiber in a dispersion or solution of a binder, and drying methods for forming and using the same are also disclosed.
Inventors
- 👤 Kazuo Izumi
- 👤 Kenzi Shimazaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:25
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249986; Y10T428/29; Y10T428/2913; Y10T428/2918
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
174 words
A filter composed of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by activating the carbon fiber with an activation gas which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber, wherein the activated carbon fiber is adhered to the substrate by a binder, and wherein the activated carbon fiber is deposited on and in the substrate by impregnating the substrate with a dispersion obtained by dispersing activated carbon fiber in a dispersion or solution of a binder, and drying, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 2
Dependent Claim
174 words
A filter composed of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by activating the carbon fiber with an activation gas which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber, wherein the activated carbon fiber is adhered to the substrate by a binder, and wherein the activated carbon fiber is deposited on and in the substrate by impregnating the substrate with a dispersion obtained by dispersing activated carbon fiber in a dispersion or solution of a binder, and drying, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 3
Dependent Claim
23 words
A filter according to claim 1, wherein the activated carbon fiber has a specific surface area of 500 m 2 /g or more.
Claim 4
Dependent Claim
23 words
A filter according to claim 1, wherein the activated carbon fiber has a specific surface area of 500 to 2,000 m 2 /g.
Claim 5
Dependent Claim
21 words
A filter according to claim 1, wherein the activated carbon fiber has a benzene adsorption rate constant of 0.2/mm or more.
Claim 6
Dependent Claim
34 words
A filter according to claim 1, wherein the activated carbon fiber has supported thereon at least one compound of a metal selected from groups Ib, IIb, VIa, VIIa and VIII of the Periodic Table.
Claim 7
Dependent Claim
32 words
A filter according to claim 5, wherein the activated carbon fiber has supported thereon 0.01 to 30 wt % of the metal compound based on the weight of the activated carbon fiber.
Claim 8
Dependent Claim
22 words
A filter according to claim 1, wherein the substrate has 5 to 200 cells or openings per 2.5 cm of the substrate.
Claim 9
Dependent Claim
18 words
A filter according to claim 1, wherein the substrate is a porous synthetic resin having continuous open cells.
Claim 10
Dependent Claim
16 words
A filter according to claim 1, wherein the substrate comprises a urethane foam or polystyrene foam.
Claim 11
Dependent Claim
13 words
A filter according to claim 1, wherein the substrate comprises a urethane foam.
Claim 12
Dependent Claim
33 words
A filter according to claim 1, wherein the activated carbon fiber is deposited on the substrate in an amount of from 10 to 200 wt % based on the weight of the substrate.
Claim 13
Dependent Claim
31 words
A filter according to claim 1, wherein the binder is selected from starch paste, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, polyacrylic acid, polyacrylamide, polystyrene, polyethylene, polyvinyl acetate, polyacrylonitrile adnm polyvinylidene chloride.
Claim 14
Dependent Claim
28 words
A filter according to claim 1, wherein the binder is used in an amount of from 0.5 to 30 wt % based on the weight of the substrate.
Claim 15
Dependent Claim
17 words
A filter according to claim 1, wherein the activated carbon fiber is derived from a polyacrylonitrile fiber.
Claim 16
Dependent Claim
18 words
A filter according to claim 1, wherein the activated carbon fiber has a diameter of 3 to 25μ.
Claim 17
Dependent Claim
163 words
A process for producing a filter comprising dispersing activated carbon fiber obtained by activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of 5 to 1,000μ in a dispersion or solution of a binder, impregnating the resulting dispersion in a mesh structure substrate to adhere the carbon fiber thereon and therein, and drying the impregnated substrate, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with the alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 18
Dependent Claim
163 words
A process for producing a filter comprising dispersing activated carbon fiber obtained by activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of 5 to 1,000μ in a dispersion or solution of a binder, impregnating the resulting dispersion in a mesh structure substrate to adhere the carbon fiber thereon and therein, and drying the impregnated substrate, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with the alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 19
Dependent Claim
19 words
A process according to claim 16, wherein said alkali is selected from the group consisting of NaOH and KOH.
Claim 20
Dependent Claim
20 words
A process according to claim 16, wherein the concentration of the aqueous solution is from 0.5 to 15% by weight.
Claim 21
Dependent Claim
45 words
A process according on claim 16, wherein the temperature of the aqueous solution is from 20° to 100° C. and the solution is applied to the activated carbon fiber by impregnating the activated carbon fiber with the aqueous solution for from 5 to 120 minutes.
Claim 22
Independent Claim
153 words
A method for removing ozone from a gas which comprises passing the gas through a filter made of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 23
Independent Claim
153 words
A method for removing ozone from a gas which comprises passing the gas through a filter made of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, the activated carbon fiber being washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 24
Dependent Claim
37 words
A filter according to claim 1 wherein the activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture thereof or a member from said group containing an inert gas.
Claim 25
Dependent Claim
36 words
The process of claim 16, wherein said activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture thereof or a member from said group containing an inert gas.
Claim 26
Dependent Claim
36 words
A method according to claim 20, wherein said activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture or a member from said group containing an inert gas.
Claim 27
Dependent Claim
49 words
A filter according to claim 1 wherein the activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture thereof or a member from said group containing an inert gas and wherein the activated carbon fiber is derived from a polyacrylonitrile fiber.
Claim 28
Dependent Claim
48 words
The process of claim 16, wherein said activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture thereof or a member from said group containing an inert gas and wherein the activated carbon fiber is derived from a polyacrylonitrile fiber.
Claim 29
Dependent Claim
48 words
A method according to claim 20, wherein said activation gas is selected from the group consisting of steam, CO 2 , NH 3 , a mixture or a member from said group containing an inert gas and wherein the activated carbon fiber is derived from a polyacrylonitrile fiber.
Claim 30
Independent Claim
159 words
A method for removing hydrogen sulfide from a gas which comprises passing the gas through a filter made of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by the process consisting of activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, wherein the activated carbon fiber is washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
Claim 31
Independent Claim
159 words
A method for removing hydrogen sulfide from a gas which comprises passing the gas through a filter made of a mesh structure substrate having deposited thereon and therein activated carbon fiber obtained by the process consisting of activating the carbon fiber with an activation gas, which activated carbon fiber is treated with an alkali and has a length within the range of from 5 to 1,000μ, wherein the mesh structure substrate has an average cell diameter 3 to 100 times the length of the activated carbon fiber and wherein the activated carbon fiber is adhered to the substrate by a binder, wherein said treatment with an alkali is conducted by applying an aqueous solution of the alkali to the activated carbon fiber, wherein the activated carbon fiber is washed with water after applying the aqueous solution of the alkali to the activated carbon fiber, the washing with water being conducted until the water used for the washing becomes neutral.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-20 | 1992-03-21 | 1992-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-20 | 1996-03-21 | 1996-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-20 | 2000-03-21 | 2000-09-20 | $7700.00 | Window Closed / Lapsed |