US5283106A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nonwoven material of two or more layers, in particular with long-term filter properties and manufacture thereof
Assignee: Hoechst AG
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Filing: 1990-12-04
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Granted: 1994-02-01
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Expires: 2010-12-04
Abstract
Abstract There is disclosed a multilayered filter material comprising nonwovens made of fibers or filaments of identical or different polymers, said filter material being composed of a depth filter and a fine filter which both have a homogeneous density perpendicular to their surface and have been joined together in such a way that the area covered by the bonding dots does not exceed 75%. The depth filter is from 2 to 20 times thicker than the fine filter, and they have different densities. There is also disclosed a process for manufacturing the filter material.
Inventors
- 👤 Kurt Seiler
- 👤 Peter Heidel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:32
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/08; B01D39/083; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/26; B01D39/14; B32B5/02; B32B5/022; B32B5/12; B32B7/00; B32B7/04; D; D04; D04H; D04H13/00; D04H3/00; D04H3/005; D04H3/009; D04H3/011; D04H3/02; D04H3/08; D04H3/12; B01D2239/00; B01D2239/04; B01D2239/0464; B01D2239/06; B01D2239/0604; B01D2239/0627; B01D2239/065; B01D2239/0659; B01D2239/0668; B01D2239/0672; B01D2239/0681; B01D2239/12; B01D2239/1291; B32B2307/00; B32B2307/70; B32B2307/718; B32B2307/72; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1089; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24298; Y10T428/24314; Y10T428/24628; Y10T428/24669; Y10T428/24686; Y10T428/24802; Y10T428/24826; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T442/00; Y10T442/60; Y10T442/659; Y10T442/66; Y10T442/668
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
171 words
A multilayered filter material comprising nonwovens made of polymer fibers or filaments, said filter material including a depth filter for filtering out particles throughout its entire depth and a fine filter for filtering out particles along its surface, both filters having a homogeneous density perpendicular to their surface and being joined together by adhesive or welding in such a way that the area so joined does not exceed 75%, the fine and depth filters each comprising a filament nonwoven with the depth filter having a thickness from 2 to 20 times greater than the fine filter, the depth filter having a basis weight from 150 to 500 g/m 2 and the fine filter having a basis weight from 30 to 100 g/m 2 , and wherein the fiber denier of the depth filter is between 4 and 20 dtex and the fiber denier of the fine filter is between 1 and 6 dtex whereby the linear densities of the fine filter are smaller than the linear densities of the depth filter.
Claim 2
Dependent Claim
171 words
A multilayered filter material comprising nonwovens made of polymer fibers or filaments, said filter material including a depth filter for filtering out particles throughout its entire depth and a fine filter for filtering out particles along its surface, both filters having a homogeneous density perpendicular to their surface and being joined together by adhesive or welding in such a way that the area so joined does not exceed 75%, the fine and depth filters each comprising a filament nonwoven with the depth filter having a thickness from 2 to 20 times greater than the fine filter, the depth filter having a basis weight from 150 to 500 g/m 2 and the fine filter having a basis weight from 30 to 100 g/m 2 , and wherein the fiber denier of the depth filter is between 4 and 20 dtex and the fiber denier of the fine filter is between 1 and 6 dtex whereby the linear densities of the fine filter are smaller than the linear densities of the depth filter.
Claim 3
Dependent Claim
19 words
The multilayered filter material as claimed in claim 1, wherein the depth filter is upstream of the fine filter.
Claim 4
Dependent Claim
17 words
The multilayered filter material as claimed in claim 1, wherein the individual layers have different packing densities.
Claim 5
Dependent Claim
17 words
The multilayered filter material as claimed in claim 1, wherein the individual layers have different fiber deniers.
Claim 6
Dependent Claim
24 words
The multilayered filter material as claimed in claim 1, wherein the multilayer filter is held together by means of an adhesive thermoplastic slit film.
Claim 7
Dependent Claim
18 words
The multilayered filter material as claimed in claim 1, wherein the filter joined area is less than 50%.
Claim 8
Dependent Claim
21 words
The multilayered filter material as claimed in claim 1, wherein the fine filter is from 0.2 to 0.6 mm in thickness.
Claim 9
Dependent Claim
25 words
The multilayered filter material as claimed in claim 1, wherein the packing density of the depth filter is from 0.08 to 0.15 g/cm 3 .
Claim 10
Dependent Claim
25 words
The multilayered filter material as claimed in claim 1, wherein the packing density of the fine filter is from 0.10 to 0.20 g/cm 3 .
Claim 11
Dependent Claim
11 words
The multilayered filter material as claimed in claim 1, possessing pleatability.
Claim 12
Dependent Claim
65 words
A process for manufacturing a multilayered filter material wherein a nonwoven fine filter for filtering out particles along its surface and a nonwoven depth filter for filtering out particles throughout its entire depth are separately produced and thermally or chemically consolidated, placed on top of one another in a subsequent step and joined together at their contact surface mechanically or by welding or with adhesive.
Claim 13
Dependent Claim
65 words
A process for manufacturing a multilayered filter material wherein a nonwoven fine filter for filtering out particles along its surface and a nonwoven depth filter for filtering out particles throughout its entire depth are separately produced and thermally or chemically consolidated, placed on top of one another in a subsequent step and joined together at their contact surface mechanically or by welding or with adhesive.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-01-31 | 1997-08-02 | 1998-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-31 | 2001-08-02 | 2002-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-31 | 2005-08-02 | 2006-02-01 | $7700.00 | Window Closed / Lapsed |